Apparatus, system and method of determining one or more optical parameters of a lens

ABSTRACT

Some demonstrative embodiments include apparatuses, systems and/or methods of determining one or more optical parameters of a lens of eyeglasses. For example, a product may include one or more tangible computer-readable non-transitory storage media including computer-executable instructions operable to, when executed by at least one computer processor, enable the at least one computer processor to process at least one captured image of at least one reflection of a flash on a lens of eyeglasses; and determine one or more optical parameters of the lens based at least on the at least one captured image.

CROSS REFERENCE

This Application claims the benefit of and priority from US ProvisionalPatent Application No. 62/286,330 entitled “APPARATUS, SYSTEM AND METHODOF DETERMINING ONE OR MORE OPTICAL PARAMETERS OF A LENS”, filed Jan. 23,2016, and is Continuation in Part of PCT application No.PCT/IB2016/052673 entitled “APPARATUS, SYSTEM AND METHOD OF DETERMININGONE OR MORE OPTICAL PARAMETERS OF A LENS”, filed May 10, 2016, which inturn claims the benefit of and priority from U.S. Provisional PatentApplication No. 62/159,295 entitled “APPARATUS, SYSTEM AND METHOD OFDETERMINING ONE OR MORE OPTICAL PARAMETERS OF A LENS”, filed May 10,2015, from U.S. Provisional Patent Application No. 62/216,757 entitled“APPARATUS, SYSTEM AND METHOD OF DETERMINING ONE OR MORE OPTICALPARAMETERS OF A LENS”, filed Sep. 10, 2015, and from U.S. ProvisionalPatent Application No. 62/286,331 entitled “APPARATUS, SYSTEM AND METHODOF DETERMINING ONE OR MORE OPTICAL PARAMETERS OF A LENS”, filed Jan. 23,2016, the entire disclosures of all of which are incorporated herein byreference.

TECHNICAL FIELD

Embodiments described herein generally relate to determining one or moreoptical parameters of a lens.

BACKGROUND

Eyeglasses and/or prescription eyeglasses may include lenses assembledin a frame of the eyeglasses.

The lenses may have one or more optical parameters. The opticalparameters of a lens may include, for example, a spherical power, acylindrical power and/or a cylindrical axis.

Determining the spherical power, the cylindrical power, and/or thecylindrical axis of the lens may be useful, for example, if a user ofthe eyeglasses wishes to duplicate the eyeglasses and/or to producespare lenses for the eyeglasses.

BRIEF DESCRIPTION OF THE DRAWINGS

For simplicity and clarity of illustration, elements shown in thefigures have not necessarily been drawn to scale. For example, thedimensions of some of the elements may be exaggerated relative to otherelements for clarity of presentation. Furthermore, reference numeralsmay be repeated among the figures to indicate corresponding or analogouselements. The figures are listed below.

FIG. 1 is a schematic block diagram illustration of a system, inaccordance with some demonstrative embodiments.

FIGS. 2A and 2B depict a first captured image and a second capturedimage, respectively, in accordance with some demonstrative embodiments.

FIG. 3 schematically illustrates a plurality of captured imagescorresponding to a plurality of tilting angles of eyeglasses, inaccordance with some demonstrative embodiments.

FIGS. 4A and 4B schematically illustrate a measurement scheme, inaccordance with some demonstrative embodiments.

FIGS. 5A and 5B depict an image of eyeglasses, in accordance with somedemonstrative embodiments

FIG. 6 depicts an image of eyeglasses, in accordance with somedemonstrative embodiments

FIG. 7 schematically illustrates a reflection scheme, in accordance withsome demonstrative embodiments.

FIG. 8 is a schematic flow-chart illustration of a method of determiningone or more optical parameters of a lens, in accordance with somedemonstrative embodiments.

FIG. 9 is a schematic illustration of a measurement scheme, inaccordance with some demonstrative embodiments.

FIG. 10 is a schematic illustration of an image of an object displayedon a display, in accordance with some demonstrative embodiments.

FIGS. 11A, 11B, and 11C and 11D are schematic illustrations of fourrespective relative magnification graphs, in accordance with somedemonstrative embodiments.

FIG. 12 is a schematic illustration of a method of determining one ormore optical parameters of a lens, in accordance with some demonstrativeembodiments.

FIG. 13 is a schematic illustration of a measurement scheme, inaccordance with some demonstrative embodiments.

FIG. 14 is a schematic flow-chart illustration of a method ofdetermining one or more optical parameters of a lens, in accordance withsome demonstrative embodiments.

FIG. 15 is a schematic illustration of a measurement scheme, inaccordance with some demonstrative embodiments.

FIG. 16 is a schematic flow-chart illustration of a method ofdetermining one or more optical parameters of a lens, in accordance withsome demonstrative embodiments.

FIG. 17 is a schematic illustration of a measurement scheme, inaccordance with some demonstrative embodiments.

FIG. 18 is a schematic flow-chart illustration of a method ofdetermining one or more optical parameters of a lens, in accordance withsome demonstrative embodiments.

FIG. 19 is a schematic illustration of a measurement scheme, inaccordance with some demonstrative embodiments.

FIG. 20 is a schematic flow-chart illustration of a method ofdetermining one or more optical parameters of a lens, in accordance withsome demonstrative embodiments.

FIG. 21 is a schematic illustration of a measurement scheme, inaccordance with some demonstrative embodiments.

FIG. 22 is a schematic illustration of a measurement scheme, inaccordance with some demonstrative embodiments.

FIG. 23 is a schematic illustration of a calibration scheme, inaccordance with some demonstrative embodiments.

FIG. 24 is a schematic illustration of an image of an object, inaccordance with some demonstrative embodiments.

FIG. 25 is a schematic illustration of an image of an object, inaccordance with some demonstrative embodiments.

FIG. 26 is a schematic illustration of an image of an object, inaccordance with some demonstrative embodiments.

FIG. 27 is a schematic illustration of an image of an object, inaccordance with some demonstrative embodiments.

FIG. 28 is a schematic illustration of an ellipse curve fit of acircular ring object, in accordance with some demonstrative embodiments.

FIG. 29 is a schematic illustration of an image of an object capturedvia two lenses of eyeglasses, in accordance with some demonstrativeembodiments.

FIG. 30 is a schematic flow-chart illustration of a method ofdetermining a pupillary distance of lenses of eyeglasses, in accordancewith some demonstrative embodiments.

FIG. 31 is a schematic flow-chart illustration of a method ofdetermining a distance between a camera and eyeglasses, in accordancewith some demonstrative embodiments.

FIG. 32 is a schematic flow-chart illustration of a method ofdetermining one or more optical parameters of a lens, in accordance withsome demonstrative embodiments.

FIG. 33 is a schematic flow-chart illustration of a method ofdetermining one or more optical parameters of a lens, in accordance withsome demonstrative embodiments.

FIG. 34 is a schematic flow-chart illustration of a method ofdetermining one or more optical parameters of a lens, in accordance withsome demonstrative embodiments.

FIG. 35 is a schematic illustration of a product, in accordance withsome demonstrative embodiments.

DETAILED DESCRIPTION

In the following detailed description, numerous specific details are setforth in order to provide a thorough understanding of some embodiments.However, it will be understood by persons of ordinary skill in the artthat some embodiments may be practiced without these specific details.In other instances, well-known methods, procedures, components, unitsand/or circuits have not been described in detail so as not to obscurethe discussion.

Some portions of the following detailed description are presented interms of algorithms and symbolic representations of operations on databits or binary digital signals within a computer memory. Thesealgorithmic descriptions and representations may be the techniques usedby those skilled in the data processing arts to convey the substance oftheir work to others skilled in the art.

An algorithm is here, and generally, considered to be a self-consistentsequence of acts or operations leading to a desired result. Theseinclude physical manipulations of physical quantities. Usually, thoughnot necessarily, these quantities capture the form of electrical ormagnetic signals capable of being stored, transferred, combined,compared, and otherwise manipulated. It has proven convenient at times,principally for reasons of common usage, to refer to these signals asbits, values, elements, symbols, characters, terms, numbers or the like.It should be understood, however, that all of these and similar termsare to be associated with the appropriate physical quantities and aremerely convenient labels applied to these quantities.

Discussions herein utilizing terms such as, for example, “processing”,“computing”, “calculating”, “determining”, “establishing”, “analyzing”,“checking”, or the like, may refer to operation(s) and/or process(es) ofa computer, a computing platform, a computing system, or otherelectronic computing device, that manipulate and/or transform datarepresented as physical (e.g., electronic) quantities within thecomputer's registers and/or memories into other data similarlyrepresented as physical quantities within the computer's registersand/or memories or other information storage medium that may storeinstructions to perform operations and/or processes.

The terms “plurality” and “a plurality”, as used herein, include, forexample, “multiple” or “two or more”. For example, “a plurality ofitems” includes two or more items.

References to “one embodiment”, “an embodiment”, “demonstrativeembodiment”, “various embodiments” etc., indicate that the embodiment(s)so described may include a particular feature, structure, orcharacteristic, but not every embodiment necessarily includes theparticular feature, structure, or characteristic. Further, repeated useof the phrase “in one embodiment” does not necessarily refer to the sameembodiment, although it may.

As used herein, unless otherwise specified the use of the ordinaladjectives “first”, “second”, “third” etc., to describe a common object,merely indicate that different instances of like objects are beingreferred to, and are not intended to imply that the objects so describedmust be in a given sequence, either temporally, spatially, in ranking,or in any other manner.

Some embodiments, for example, may capture the form of an entirelyhardware embodiment, an entirely software embodiment, or an embodimentincluding both hardware and software elements. Some embodiments may beimplemented in software, which includes but is not limited to firmware,resident software, microcode, or the like.

Furthermore, some embodiments may capture the form of a computer programproduct accessible from a computer-usable or computer-readable mediumproviding program code for use by or in connection with a computer orany instruction execution system. For example, a computer-usable orcomputer-readable medium may be or may include any apparatus that cancontain, store, communicate, propagate, or transport the program for useby or in connection with the instruction execution system, apparatus, ordevice.

In some demonstrative embodiments, the medium may be an electronic,magnetic, optical, electromagnetic, infrared, or semiconductor system(or apparatus or device) or a propagation medium. Some demonstrativeexamples of a computer-readable medium may include a semiconductor orsolid state memory, magnetic tape, a removable computer diskette, arandom access memory (RAM), a read-only memory (ROM), a FLASH memory, arigid magnetic disk, and an optical disk. Some demonstrative examples ofoptical disks include compact disk-read only memory (CD-ROM), compactdisk-read/write (CD-R/W), and DVD.

In some demonstrative embodiments, a data processing system suitable forstoring and/or executing program code may include at least one processorcoupled directly or indirectly to memory elements, for example, througha system bus. The memory elements may include, for example, local memoryemployed during actual execution of the program code, bulk storage, andcache memories which may provide temporary storage of at least someprogram code in order to reduce the number of times code must beretrieved from bulk storage during execution.

In some demonstrative embodiments, input/output or I/O devices(including but not limited to keyboards, displays, pointing devices,etc.) may be coupled to the system either directly or throughintervening I/O controllers. In some demonstrative embodiments, networkadapters may be coupled to the system to enable the data processingsystem to become coupled to other data processing systems or remoteprinters or storage devices, for example, through intervening private orpublic networks. In some demonstrative embodiments, modems, cable modemsand Ethernet cards are demonstrative examples of types of networkadapters. Other suitable components may be used.

Some embodiments may include one or more wired or wireless links, mayutilize one or more components of wireless communication, may utilizeone or more methods or protocols of wireless communication, or the like.Some embodiments may utilize wired communication and/or wirelesscommunication.

Some embodiments may be used in conjunction with various devices andsystems, for example, a mobile phone, a Smartphone, a mobile computer, alaptop computer, a notebook computer, a tablet computer, a handheldcomputer, a handheld device, a Personal Digital Assistant (PDA) device,a handheld PDA device, a mobile or portable device, a non-mobile ornon-portable device, a cellular telephone, a wireless telephone, adevice having one or more internal antennas and/or external antennas, awireless handheld device, or the like.

Reference is now made to FIG. 1, which schematically illustrates a blockdiagram of a system 100, in accordance with some demonstrativeembodiments.

As shown in FIG. 1, in some demonstrative embodiments system 100 mayinclude a computing device 102.

In some demonstrative embodiments, device 102 may be implemented usingsuitable hardware components and/or software components, for example,processors, controllers, memory units, storage units, input units,output units, communication units, operating systems, applications, orthe like.

In some demonstrative embodiments, device 102 may include, for example,a computing device, a mobile phone, a Smartphone, a Cellular phone, anotebook, a mobile computer, a laptop computer, a notebook computer, atablet computer, a handheld computer, a handheld device, a PDA device, ahandheld PDA device, a wireless communication device, a PDA device whichincorporates a wireless communication device, or the like.

In some demonstrative embodiments, device 102 may include, for example,one or more of a processor 191, an input unit 192, an output unit 193, amemory unit 194, and/or a storage unit 195. Device 102 may optionallyinclude other suitable hardware components and/or software components.In some demonstrative embodiments, some or all of the components of oneor more of device 102 may be enclosed in a common housing or packaging,and may be interconnected or operably associated using one or more wiredor wireless links. In other embodiments, components of one or more ofdevice 102 may be distributed among multiple or separate devices.

In some demonstrative embodiments, processor 191 may include, forexample, a Central Processing Unit (CPU), a Digital Signal Processor(DSP), one or more processor cores, a single-core processor, a dual-coreprocessor, a multiple-core processor, a microprocessor, a hostprocessor, a controller, a plurality of processors or controllers, achip, a microchip, one or more circuits, circuitry, a logic unit, anIntegrated Circuit (IC), an Application-Specific IC (ASIC), or any othersuitable multi-purpose or specific processor or controller. Processor191 may execute instructions, for example, of an Operating System (OS)of device 102 and/or of one or more suitable applications.

In some demonstrative embodiments, input unit 192 may include, forexample, a keyboard, a keypad, a mouse, a touch-screen, a touch-pad, atrack-ball, a stylus, a microphone, or other suitable pointing device orinput device. Output unit 193 may include, for example, a monitor, ascreen, a touch-screen, a flat panel display, a Light Emitting Diode(LED) display unit, a Liquid Crystal Display (LCD) display unit, aplasma display unit, one or more audio speakers or earphones, or othersuitable output devices.

In some demonstrative embodiments, memory unit 194 includes, forexample, a Random Access Memory (RAM), a Read Only Memory (ROM), aDynamic RAM (DRAM), a Synchronous DRAM (SD-RAM), a flash memory, avolatile memory, a non-volatile memory, a cache memory, a buffer, ashort term memory unit, a long term memory unit, or other suitablememory units. Storage unit 195 may include, for example, a hard diskdrive, a floppy disk drive, a Compact Disk (CD) drive, a CD-ROM drive, aDVD drive, or other suitable removable or non-removable storage units.Memory unit 194 and/or storage unit 195, for example, may store dataprocessed by device 102.

In some demonstrative embodiments, device 102 may be configured tocommunicate with one or more other devices via a wireless and/or wirednetwork 103.

In some demonstrative embodiments, network 103 may include a wirednetwork, a local area network (LAN), a wireless LAN (WLAN) network, aradio network, a cellular network, a Wireless Fidelity (WiFi) network,an IR network, a Bluetooth (BT) network, and the like.

In some demonstrative embodiments, device 102 may allow one or moreusers to interact with one or more processes, applications and/ormodules of device 102, e.g., as described herein.

In some demonstrative embodiments, device 102 may be configured toperform and/or to execute one or more operations, modules, processes,procedures and/or the like.

In some demonstrative embodiments, device 102 may be configured todetermine a one or more optical parameters of a lens of eyeglasses,e.g., provided by a user of device 102, e.g., as described below.

In some demonstrative embodiments, system 100 may be configured toperform lensmeter or lensometer analysis of the lens of the eyeglasses,for example, even without using any auxiliary optical means, e.g., asdescribed below.

In some demonstrative embodiments, the one or more optical parameters ofthe lens may include a spherical power, a cylindrical power and/or acylindrical axis of the lens.

In some demonstrative embodiments, system 100 may be configured toanalyze a focal power of a spherical lens, a focal power and acylindrical axis of a cylindrical lens, a distance between the centersof two lenses assembled in a frame of the eyeglasses, and/or any otheroptical parameters of the lens, e.g., as described below.

In some demonstrative embodiments, system 100 may include at least oneservice, module, controller, and/or application 160 configured todetermine the one or more optical parameters of the lens provided by theuser of device 102, e.g., as described below.

In some demonstrative embodiments, application 160 may include and/ormay perform the functionality of a lensometer module, e.g., configuredto perform the lensmeter or lensometer analysis of the lens of theeyeglasses.

In some demonstrative embodiments, application 160 may include, or maybe implemented as, software, a software module, an application, aprogram, a subroutine, instructions, an instruction set, computing code,words, values, symbols, and the like.

In some demonstrative embodiments, application 160 may include a localapplication to be executed by device 102. For example, memory unit 194and/or storage unit 195 may store instructions resulting in application160, and/or processor 191 may be configured to execute the instructionsresulting in application 160, e.g., as described below.

In other embodiments, application 160 may include a remote applicationto be executed by any suitable computing system, e.g., a server 170.

In some demonstrative embodiments, server 170 may include at least aremote server, a web-based server, a cloud server, and/or any otherserver.

In some demonstrative embodiments, the server 170 may include a suitablememory and/or storage unit 174 having stored thereon instructionsresulting in application 160, and a suitable processor 171 to executethe instructions, e.g., as descried below.

In some demonstrative embodiments, application 160 may include acombination of a remote application and a local application.

In one example, application 160 may be downloaded and/or received by theuser of device 102 from another computing system, e.g., server 170, suchthat application 160 may be executed locally by users of device 102. Forexample, the instructions may be received and stored, e.g., temporarily,in a memory or any suitable short-term memory or buffer of device 102,e.g., prior to being executed by processor 191 of device 102.

In another example, application 160 may include a front-end to beexecuted locally by device 102, and a backend to be executed by server170. For example, one or more first operations of determining the one ormore optical parameters of the lens of the user may be performedlocally, for example, by device 102, and/or one or more secondoperations of determining the one or more optical parameters may beperformed remotely, for example, by server 170, e.g., as describedbelow.

In other embodiments, application 160 may include any other suitablecomputing arrangement and/or scheme.

In some demonstrative embodiments, system 100 may include an interface110 to interface between a user of device 102 and one or more elementsof system 100, e.g., application 160.

In some demonstrative embodiments, interface 110 may be implementedusing any suitable hardware components and/or software components, forexample, processors, controllers, memory units, storage units, inputunits, output units, communication units, operating systems, and/orapplications.

In some embodiments, interface 110 may be implemented as part of anysuitable module, system, device, or component of system 100.

In other embodiments, interface 110 may be implemented as a separateelement of system 100.

In some demonstrative embodiments, interface 110 may be implemented aspart of device 102. For example, interface 110 may be associated withand/or included as part of device 102.

In one example, interface 110 may be implemented, for example, asmiddleware, and/or as part of any suitable application of device 102.For example, interface 110 may be implemented as part of application 160and/or as part of an OS of device 102.

In some demonstrative embodiments, interface 160 may be implemented aspart of server 170. For example, interface 110 may be associated withand/or included as part of server 170.

In one example, interface 110 may include, or may be part of a Web-basedapplication, a web-site, a web-page, a plug-in, an ActiveX control, arich content component (e.g., a Flash or Shockwave component), or thelike.

In some demonstrative embodiments, interface 110 may be associated withand/or may include, for example, a gateway (GW) 112 and/or anapplication programming interface (API) 114, for example, to communicateinformation and/or communications between elements of system 100 and/orto one or more other, e.g., internal or external, parties, users,applications and/or systems.

In some embodiments, interface 110 may include any suitableGraphic-User-Interface (GUI) 116 and/or any other suitable interface.

In some demonstrative embodiments, system 100 may include a display 130configured to display one or more objects to be captured by an imagecapturing device, and/or to display information, objects, instructionsand/or any other content, for example, to a user, e.g., as describedbelow.

In some demonstrative embodiments, display 130 may include a separatedisplay, a stand-alone display and/or a display device, e.g., separatefrom other elements of system 100.

In some demonstrative embodiments, display 130 may be part of device 102or part of server 170.

In some demonstrative embodiments, display 130 may be part of any othercomputing system, e.g., a laptop, a desktop, and/or the like.

In some demonstrative embodiments, display 130 may include, for example,a monitor, a screen, a touch-screen, a flat panel display, a LED displayunit, an LCD display unit, a plasma display unit, one or more audiospeakers or earphones, and/or any other suitable components.

In some demonstrative embodiments, the GUI 116 of interface 110 may bedisplayed on display 130.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of the lens, for example,based on at least one captured image, e.g., as described below.

In some demonstrative embodiments, device 102 may include an imagecapturing device, e.g., a camera 118, or any other device, configured tocapture the at least one image.

In some demonstrative embodiments, application 160 may be configured tocontrol, cause, trigger, and/or instruct camera 118 to capture the atleast one captured.

In some demonstrative embodiments, application 160 may be configured toinstruct a user of device 102 to capture the captured image.

In some demonstrative embodiments, application 160 may be configured toreceive the at least one captured image, e.g., directly or indirectlyfrom the camera 118.

In one example, application 160 may be configured to determine the oneor more optical parameters of the lens locally, for example, ifapplication 160 is locally implemented by device 102. According to thisexample, camera 118 may be configured to capture the image, andapplication 160 may be configured to receive the captured image, e.g.,from camera 118, and to determine the one or more optical parameters ofthe lens, e.g., as described below.

In another example, application 160 may be configured to determine theone or more optical parameters of the lens remotely, for example, ifapplication 160 is implemented by server 170, or if the back-end ofapplication 160 is implemented by server 170, e.g., while the front-endof application 160 is implemented by device 102. According to thisexample, camera 118 may be configured to capture the image; thefront-end of application 160 may be configured to receive the capturedimage; and server 170 and/or the back-end of application 160 may beconfigured to determine the one or more optical parameters of the lens,e.g., based on information received from the front-end of application160.

In one example, device 102 and/or the front-end of application 160 maybe configured to send the captured image and, optionally, additionalinformation, e.g., as described below, to server 170, e.g., via network103; and/or server 170 and/or the back-end of application 160 may beconfigured to receive the captured image, and to determine the one ormore optical parameters of the lens, for example, based on the capturedimage from device 102.

In some demonstrative embodiments, the at least one captured image mayinclude at least one reflection of a flash on a lens of eyeglasses.

In some demonstrative embodiments, application 160 may be configured tocontrol, cause, trigger, and/or instruct camera 118 to capture the atleast one captured image including the at least one reflection of theflash on the lens of eyeglasses.

In some demonstrative embodiments, application 160 may be configured toinstruct a user of device 102 to capture the captured image to includethe at least one reflection of the flash on the lens of eyeglasses.

In some demonstrative embodiments, application 160 may be configured toinstruct the user of device 102 to capture the at least one capturedimage, for example, while tilting the eyeglasses, for example, whilecausing device 102 to capture a plurality of images, e.g., as describedbelow.

In other embodiments, the at least one captured image may include atleast one reference object captured via the lens of the eyeglasses,e.g., as described below.

In one example, the at least one captured image may include both the atleast one reference object captured via the lens of the eyeglasses andthe at least one reflection of the flash on the lens of the eyeglasses,e.g., as described below.

In another example, the at least one captured image may include aplurality of captured images For example, a first captured image mayinclude the at least one reference object captured via the lens of theeyeglasses, and a second captured image may include the at least onereflection of the flash on the lens of the eyeglasses. According to thisexample, the first and second images may be captured sequentially, forexample, the second image may be captured after the first image, or thefirst image may be captured after the second image.

In some demonstrative embodiments, the at least one reflection mayinclude a first reflection of the flash from a front surface of thelens, and a second reflection of the flash from a back surface of thelens, e.g., as described below

In some demonstrative embodiments, device 102 may include a flash device122 configured to produce a flash-light (“flash”), which may bereflected on the lens of the eyeglasses, e.g., when the captured imageis captured.

In one example, application 160 may be configured to control, cause,trigger, and/or instruct flash device 122 to produce the flash, forexample, when the captured image is captured.

In another example, application 160 may be configured to instruct theuser of device 102 to capture the captured image using flash device 122.

In some demonstrative embodiments, flash device 122 may include a flashlamp, a light emitting diode (LED), and/or any other light source.

In some demonstrative embodiments, application 160 may be configured toprocess the at least one captured image of the at least one reflectionof the flash, e.g., from flash device 122, on the lens of theeyeglasses, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine one or more optical parameters of the lens based at least onthe at least one captured image, e.g., as described below.

In some demonstrative embodiments, the one or more optical parametersmay include at least a spherical power of the lens, e.g., as describedbelow.

In some demonstrative embodiments, the one or more optical parametersmay include a cylindrical power and/or a cylindrical axis of the lens,e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of the lens, for example,based on the at least one reflection and a relative angle between aplane of the lens and a plane of the camera 118, e.g., as describedbelow.

In some demonstrative embodiments, application 160 may be configured todetermine the relative angle, for example, based on the at least onereflection, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the relative angle, for example, based on at least onedisplacement between the first reflection of the flash on the frontsurface of the lens and the second reflection of the flash on the backsurface of the lens, e.g., as described below.

In some demonstrative embodiments, the at least one displacement mayinclude a vertical displacement and/or a horizontal displacement, e.g.,between the first and second reflections, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the relative angle, for example, based on a relative locationof the at least one reflection relative to a center of the lens, e.g.,as described below.

In one example, application 160 may be configured to determine therelative angle, for example, based on a first relative location of thefirst reflection relative to the center of the lens and/or a secondrelative location of the second reflection relative to the center of thelens, e.g., as described below.

In another example, application 160 may be configured to determine therelative angle, for example, based on a location of the first reflectionrelative to the second reflection, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the center of the lens, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the center of the lens, for example, based on a firstreference object image of a first reference object captured via the lensin the captured image and a second reference object image of a secondreference object captured not via the lens in the captured image, e.g.,as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of the lens, for example,based on one or more estimated optical parameters of the lens, e.g., asdescribed below.

In some demonstrative embodiments, the relative angle may be used toapply a correction factor, for example, to the estimated opticalparameters of the lens, e.g., by analyzing an aberration created from atilt of the lens, for example, based at least on the first and secondreflections, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more estimated optical parameters of the lens, forexample, based on the captured image, e.g., as described below.

In some demonstrative embodiments, the captured image may include areference object image of a reference object captured via the lens.

In one example, the reference object may be displayed on display 130,e.g., as described below.

In one example, the reference object may include a predefined object,e.g., an object drawn on a paper, a cardboard object, or the like.

In another example, the reference object may include an object displayedon a screen of device 102, e.g., a display of a Smartphone, andreflected from a mirror. According to this example, the captured imagemay include the reflection of the object in the mirror captured via thelens of the eyeglasses.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more estimated optical parameters of the lens, forexample, based on a comparison between the reference object and thereference object image, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more estimated optical parameters of the lens, forexample, based on the relative angle and the one or more estimatedoptical parameters, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine an estimated spherical power of the lens, for example, basedon a magnification between a reference dimension of the reference objectand an imaged dimension of the reference dimension in the referenceobject image, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the spherical power of the lens, for example, based on therelative angle and the estimated spherical power, e.g., as describedbelow.

In some demonstrative embodiments, application 160 may be configured todetermine an estimated cylindrical power of the lens and/or an estimatedaxis of the lens, for example, based on a deformation between one ormore reference dimensions of the reference object and one or morerespective imaged dimensions of the one or more reference dimensions inthe reference object image, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the cylindrical power of the lens and/or the cylindrical axisof the lens, for example, based on the relative angle and the estimatedcylindrical power and/or the estimated cylindrical axis, e.g., asdescribed below.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of the lens, for example,based on the one or more estimated optical parameters of the lens, forexample, even without using the relative angle, e.g., without applyingthe correction factor to the estimated optical parameters of the lens,e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of the lens, for example,based on a comparison between the reference object and the referenceobject image when the first and second reflections coincide in thecaptured image, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured totrigger an instruction to the user of device 102 to rotate theeyeglasses at least until the first and second reflections coincide,e.g., to allow to determine the one or more estimated optical parametersof the lens, for example, even without using the relative angle.

In some demonstrative embodiments, two reflections may be observed,e.g., a front reflection from the front surface of the lens and a backreflection from the back surface of the lens, for example, to allowtilting the lens with respect to the flash to a required angle.

In one example, when the lens plane is exactly parallel to the deviceplane, the two reflections, e.g., the front reflection and the backreflection, may overlap.

In some demonstrative embodiments, a bright reflection might beobserved, for example, when relatively flat surfaces are involved.

In some demonstrative embodiments, a very bright light reflection mayindicate that the lens plane is parallel with the camera plane.

In some demonstrative embodiments, two reflections that are separatedeither horizontally, vertically or both, may indicate the lens is to betilted until both reflections coincide. In one example, a horizontalseparation between the reflections may indicate to tilt the lens on thevertical axis. In another example, a vertical separation between thereflections may indicate to tilt the lens on the horizontal axis, e.g.,as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of the lens, for example,based on the at least one captured image including the at least onereflection of the flash, for example, even without using the relativeangle, e.g., as descried below.

In some demonstrative embodiments, application 160 may be configured todetermine a spherical power of the lens, for example, based on adiameter size of the at least one reflection in the image, e.g., asdescribed below.

In some demonstrative embodiments, application 160 may be configured todetermine a cylindrical power of the lens and/or a cylindrical axis ofthe lens, for example, based on a deformation of the at least onereflection in the image, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of the lens, for example,based on the at least one image including at least one reference objectcaptured via the lens of the eyeglasses, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured totrigger capturing of at least one image by camera 118 of at least onereference object via the lens of the eyeglasses.

In one example, application 160 may be configured to instruct the userof device 102 to capture the least one image of the at least onereference object via the lens of the eyeglasses e.g., as describedbelow.

In some demonstrative embodiments, application 160 may be configured todetermine a relative angle between a plane of the lens and a plane ofthe camera 118.

In some demonstrative embodiments, application 160 may be configured todetermine one or more optical parameters of the lens based at least onthe relative angle and the at least one image, e.g., as described below.

In one example, application 160 may be configured to determine or toprocesses information indicative of a relative angle between flash 122and camera 118, for example, if camera 118 and flash 122 are not on thesame plane. According to this example, application 160 may be configuredto determine the one or more optical parameters using the relativelocation and/or angle between flash 122 and camera 118.

In some demonstrative embodiments, application 160 may be configured todetermine the relative angle, for example, based on a comparison betweenthe reference object and at least one object image of the referenceobject in the at least one image.

In some demonstrative embodiments, application 160 may be configured todetermine the relative angle, for example, based on the comparisonbetween the reference object and the at least one object image of thereference object in the at least one image, for example, even withoutusing any reflections of a flash from the lens, e.g., as describedbelow.

In some demonstrative embodiments, the relative angle may be used todetermine a correction factor to one or more estimated opticalparameters of the lens, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine one or more estimated optical parameters of the lens, e.g., asdescribed below.

In some demonstrative embodiments, the at least one image may include atleast one reflection of a flash on the lens.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more estimated optical parameters of the lens, forexample, based on the at least one reflection.

In one example, application 160 may be configured to determine anestimated spherical power of the lens, for example, based on a diametersize of the at least one reflection in the image, e.g., as describedbelow.

In another example, application 160 may be configured to determine anestimated cylindrical power of the lens and/or an estimated cylindricalaxis of the lens, for example, based on a deformation of the at leastone reflection in the image, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of the lens, for example,based on the relative angle and the one or more estimated opticalparameters of the lens.

In one example, the captured image may include the at least one objectimage of the reference object and the at least one reflection. Accordingto this example, application 160 may determine the one or more opticalparameters of the lens, for example, based on one or more estimatedoptical parameters of the lens, which may be determined, for example,based on the at least one reflection in the/or captured image, and therelative angle, which may be determined, for example, based on thecomparison between the reference object and the at least one objectimage.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more estimated optical parameters of the lens, forexample, based on the comparison between the reference object and the atleast one object image in the captured image, e.g., as described below.

In one example, application 160 may determine an estimated sphericalpower of the lens based on a magnification between a reference dimensionof the reference object and an imaged dimension of the referencedimension in the image, e.g., as described below.

In another example, application 160 may determine an estimatedcylindrical power of the lens and/or an estimated cylindrical axis ofthe lens, for example, based on a deformation between one or morereference dimensions of the reference object and one or more respectiveimaged dimensions of the two or more reference dimensions in the image,e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the relative angle, for example, based on the at least tworeflections, e.g., even without using the comparison between thereference object and the at least one object image in the capturedimage, e.g., as described above.

In one example, application 160 may be configured to determine therelative angle, for example, based on the at least two reflections, forexample, by determining a distance between the two reflections, anddetermining the relative angle based on the distance between the tworeflections.

In one example, the captured image may include the at least one objectimage of the reference object and the at least one reflection. Accordingto this example, application 160 may determine the one or more opticalparameters of the lens, for example, based on the one or more estimatedoptical parameters of the lens, which may be determined, for example,based on the comparison between the reference object and the objectimage, and the relative angle, which may be determined, for example,based on the at least one reflection in the captured image.

In some demonstrative embodiments, one or more observed opticalparameters of a lens may change, for example, when the lens is observedby a camera from a relative angle, e.g., between a plane of the lens anda plane of the camera, which is not a zero angle.

In one example, an observed spherical power may be different from anominal spherical power of the lens, for example, if the spherical poweris observed from a relative angle, which is different that a zero angle.

In another example, an observed cylindrical component of the lens, e.g.,a cylindrical power of the lens and/or a cylindrical axis of the lens,may vary, for example, due to the relative angle between the plane ofthe lens and the plane of the camera.

In some demonstrative embodiments, the relative angle may be extracted,and a correction factor may be set based on the relative angle, forexample, to refine the one or more optical parameters of the lens.

In some demonstrative embodiments, when capturing an image, e.g., bycamera 118, of the lens using a flash, e.g., flash 122, the flash may bereflected from a front surface of the lens or a back surface of thelens. In one example, one or more secondary reflections may occur aswell.

In some demonstrative embodiments, one or more reflections of the flash,e.g., from the front surface of the lens or the back surface of thelens, may be described as a virtual or a real image of the flash, whichmay be created, for example, by a curvature of a surface of the lens,which may act as a mirror, e.g., to reflect the flash.

In some demonstrative embodiments, locations of the one or morereflections with respect to a center of the lens, e.g., an angle and/ora distance from the center of the lens, may suggest the relative anglebetween the plane of the camera and the plane of the lens.

In one example, for a relative angle that is equal to zero, a locationof a reflection of the flash may be exactly on the center of the lens,e.g., assuming the flash is close to a camera lens of the camera and adistance of the lens is far greater than a camera Effective Focal Lengthcamera (EFL) of the camera, e.g., camera 118.

Reference is made to FIGS. 2A and 2B, which depict a first capturedimage 200 and a second captured image 220, in accordance with somedemonstrative embodiments.

In one example, one or more elements of FIG. 1 may be arranged and/oroperated according to the captured image 220, one or more parameters maybe determined by application 160 (FIG. 1) based on captured image 220,and/or one or more measurements may be performed by one or more elementsof FIG. 1 using captured image 220, e.g., as described below.

In some demonstrative embodiments, captured images 200 and 220 may becaptured by a camera, e.g., camera 118 (FIG. 1).

In some demonstrative embodiments, as shown in FIGS. 2A and 2B, capturedimage 200 may include an image of a display 230 displaying an object240. For example, display 230 may perform the functionality of display130 (FIG. 1).

In some demonstrative embodiments, as shown in FIG. 2B, captured image220 may include an image of eyeglasses including two lenses 210.

In some demonstrative embodiments, object 240 may include one or moreknown objects, e.g., having predefined and/or knows sizes and/ordimensions.

In some demonstrative embodiments, as shown in FIG. 2A, object 240 mayinclude one or more objects 224 to be captured not via lens 210, and/orone or more objects 226 to be captured via lens 210.

In some demonstrative embodiments, one or more optical parameters of thelens 210, e.g., a spherical power, a cylindrical power and/or acylindrical axis of lens 210, may be determined, for example, based on amagnification, for example, caused by lens 210, e.g., as describedbelow.

In one example, the magnification may be determined based on comparisonbetween dimensions of objects 224 and 226, and imaged dimensions ofobjects 224 and 226 in captured image 220, e.g., as described below.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to determine a center 206 of lens 210, e.g., as describedbelow.

In some demonstrative embodiments, center 206 may be determined, forexample, based on an object 224 and an object 226, and an image 225 ofan object 226 and an image of object 224 in captured image 200.

In some demonstrative embodiments, object 224 and one or more dimensionsof the object 204 may be known and/or predefined and may not be capturedvia lens 210, and therefore, the image of object 224 may not be affectedby lens 210.

In some demonstrative embodiments, object 226 and one or more dimensionsof the object 226 may be known and/or predefined and may be captured vialens 210, and therefore, the one or more dimensions of the object 226may be changed in size and/or a location in the image 225 relative totheir original location in object 226.

In some demonstrative embodiments, center 206 may be determined, forexample, based on an axis of lens 210; locations, e.g., coordinates, ofobjects 224 and/or 226; locations e.g., coordinates, of image 225 ofobject 226 and/or the image of object 224; and a magnification of lens210, for example, for a primary axis and/or a secondary axis of lens210, e.g., for a sphero-cylindrical lens, e.g., as described below.

In some demonstrative embodiments, as shown in FIG. 2B, captured image220 may be captured while a flash of the camera is activated.

In some demonstrative embodiments, as shown in FIG. 2, the flash may bereflected on a lens 210 in a first reflection 201 and/or a secondreflection 202.

In some embodiments, first reflection 201 and/or second reflection 202may be identified, for example, based on image processing of capturedimage 200.

In some demonstrative embodiments, as shown in FIG. 2, first reflection201 and/or second reflection 202 may deviate from lens center 206, e.g.,in the X-axis and/or in the Y-axis, e.g., in different amplitudes.

In some demonstrative embodiments, as shown in FIG. 2, object 240 may bebehind the eyeglasses, and the eyeglasses are tilted at a relative anglebetween the plane of the lens 210 and a plane of the camera, e.g., whencaptured image 200 is captured.

In some demonstrative embodiments, as shown in FIG. 2, the eyeglassesare tilted in the X-axis and the Y-axis, which may cause the deviationof first reflection 201 and/or second reflection 202 from center 206.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to determine a first reflection vector 217, for example,between center 206 of lens 210 and first reflection 201, e.g., asdescribed below.

In some demonstrative embodiments, first vector 217 may include adistance (“amplitude”) between center 206 of lens 210 and firstreflection 201, and a vector angle between center 206 of lens 210 andfirst reflection 201.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to determine a second reflection vector 219, for example,between center 206 of lens 210 and second reflection 201, e.g., asdescribed below.

In some demonstrative embodiments, second reflection vector 219 mayinclude a distance between center 206 of lens 210 and second reflection202, and a vector angle between center 206 of lens 210 and secondreflection 202.

In some demonstrative embodiments, a reflection vector corresponding toa reflection, for example, representing the distance, the amplitude,and/or the angle of the reflection from the center of the lens, may bedetermined, for example, based on the imaged reflection, and/or thecalculated and/or given center of the lens, e.g., as described below.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to determine the relative angle between the plane of the lens210 and the plane of the camera, for example, when captured image 220 iscaptured, e.g., as described below.

In some demonstrative embodiments, the relative angle may be determinedfor example, based on one or more calculated or provided opticalparameters, e.g., lens spherical power, cylindrical power and/or axis,and/or reflection vectors, e.g., vectors 217 and 219, e.g., as describedbelow.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to refine one or more estimated optical parameters, forexample, based on an effect on the observed lens power, cylindricalpower and/or axis of lens 210, e.g., by the relative angle between theplane of the lens 210 and the plane of the camera.

In some demonstrative embodiments, a dioptric matrix, denoted F, may beexpressed, e.g., as follows:

$\begin{matrix}{F = {\begin{pmatrix}P_{x} & P_{t} \\P_{t} & P_{y}\end{pmatrix} = \begin{pmatrix}{S + {C\mspace{11mu}{\sin^{2}(\varphi)}}} & {{- C}\mspace{11mu}{\sin(\varphi)}{\cos(\varphi)}} \\{{- C}\mspace{11mu}{\sin(\varphi)}{\cos(\varphi)}} & {S + {C\mspace{11mu}{\cos^{2}(\varphi)}}}\end{pmatrix}}} & (1)\end{matrix}$wherein S denotes a spherical power of the lens, C denotes a cylindricalpower of the lens.

In some demonstrative embodiments, a dioptric matrix, denoted F_(tilted)for a lens tilted at a relative angle, denoted Φ, may be determined,e.g., as follows:

$\begin{matrix}{F_{tilted} = {\Phi\; F\;\Phi}} & (2) \\{{{whererin}\mspace{14mu}\Phi} = {\sqrt{1 + \frac{\sin^{2}(\theta)}{2n}}\begin{pmatrix}1 & 1 \\0 & {1/{\cos(\theta)}}\end{pmatrix}}} & (3)\end{matrix}$

In some demonstrative embodiments, the spherical power S of the lens,the cylindrical power C of the lens, and/or the angle ΦF may be deduced,for example, based on the dioptric matrix F_(tilted), e.g., as describedbelow.

In some demonstrative embodiments, a captured image, e.g., capturedimage 220, may include a single reflection of the flash.

In some demonstrative embodiments, the single reflection may enable tocalculate the relative angle between a plane of the camera and a planeof the lens, for example, if a reflection vector, e.g., reflectionsvectors 217 and/or 219, and/or or a lens center, e.g., lens center 206,are calculated or provided.

In some demonstrative embodiments, a lens curvature may be determinedaccording to a measured or a provided spherical power of the lens, forexample, based on a lens maker equation, e.g., as follows:

$\begin{matrix}{\frac{1}{f} = {\left( {n - 1} \right)\left( {\frac{1}{R_{1}} - \frac{1}{R_{2}}} \right)}} & (4)\end{matrix}$wherein R₁ denotes a radius of a back surface of the lens, and R₂denotes a radius of a front surface of the lens.

In some demonstrative embodiments, radius R₁ may be assumed to beinfinity, and the radius R₂ may be calculated, for example, according toa given and/or a measured power of the lens.

In some demonstrative embodiments, the power of the lens at a relativeangle may be determined, for example, according to a change inmagnification of one or more objects, e.g., objects 226, captured viathe lens, for example, when the image is captured.

In some demonstrative embodiments, a captured image, e.g., capturedimage 220, may include two reflections of the flash.

In some demonstrative embodiments, when the power of the lens at therelative angle of acquisition is given, each reflection may be relatedto another radius of the lens, e.g. as described below.

In some demonstrative embodiments, a first reflection may be related toa front surface of the lens, and may be created from the curvature ofthe front surface, for example, based on the radius R₂, e.g., 2/R₂.

In some demonstrative embodiments, a second reflection may be a resultof the first reflection being impacted from the front surface on theback surface.

In some demonstrative embodiments, the second reflection may correlatewith the radius R₂, e.g., a double power of a mirror with a curvatureequal to 1/R₂, e.g., if R₁ is equal to infinity.

In some demonstrative embodiments, for a curvature of a lens in thefront and back surfaces, the power of the second reflection may becorrelated to a mirror power, e.g., as follows:

$\begin{matrix}{\frac{1}{f} = {{\frac{1}{R_{1}} - \frac{n - 1}{R_{2}} + \frac{1}{R_{1}}} = {\frac{2}{R_{1}} - \frac{n - 1}{R_{2}}}}} & (5)\end{matrix}$

In some demonstrative embodiments, the eyeglasses may be tilted, e.g.,to one or more relative angles, and one or more images corresponding tothe one or more relative angles may be captured, for example, tominimize an error in an angle correction, e.g., given that a nominalspherical power and/or a cylindrical power may remain constant for everyrelative angle, e.g., as described below.

In some demonstrative embodiments, a relative angle between the plane ofthe lens and the plane of the camera may be changed, for example, bytilting the camera and recording a camera angle, denoted delta_angle, ofthe camera, for example, based on gyroscope sensor of the camera and/orany other orientation sensor.

In some demonstrative embodiments, a plurality of data pointscorresponding to a plurality of camera angles delta_angle may be used,for example, to extract a refractive index of the lens.

In some demonstrative embodiments, a relative angle between the plane ofthe lens and the plane of the camera may be changed, for example, bytilting the eyeglasses.

In some demonstrative embodiments, application 160 may be configured toinstruct the user of device 102 to capture the at least one capturedimage, for example, while tilting the eyeglasses, for example, whilecausing device 102 to capture a plurality of images, e.g., as describedbelow.

In some demonstrative embodiments, application 160 may be configured toinstruct the user of device 102 to capture a plurality of images, forexample, while tilting the eyeglasses in a plurality of tilting angles.For example, a first image of the plurality of images may be captured ina first tilting angle of the eyeglasses, and a second image of theplurality of images may be captured in a second, e.g., different,tilting angle of the eyeglasses.

In one example, device 102 may cause camera 118 to capture a sequence ofimages while the user is tilting the eyeglasses. In another example, theuser may capture the plurality of images, for example, by operatingcamera 118.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters the lens, for example,based on the plurality of captured images, which correspond to theplurality of tilting angles.

Reference is made to FIG. 3, which schematically illustrates a pluralityof captured images corresponding to a plurality of tilting angles ofeyeglasses.

In some demonstrative embodiments, as shown in FIG. 3, the plurality ofcaptured images may include an object 340, e.g., object 240 (FIG. 2),behind a lens 320 of the eyeglasses.

In some demonstrative embodiments, as shown in FIG. 3, one or moreelements of object 340 may be captured via lens 320, e.g., at theplurality of the tilting angles.

In some demonstrative embodiments, as shown in FIG. 3, a plurality ofarrows 312 may correspond to the plurality of tilting angle of theeyeglasses.

In some demonstrative embodiments, as shown in FIG. 3, a lens center 306of lens 320 may be marked on lens 310.

In some demonstrative embodiments, as shown in FIG. 3, a plurality ofreflection vectors 317 between center of lens 306 and a plurality offirst reflections 301 on lens 310 may be marked.

In some demonstrative embodiments, there may be a relationship between atilting angle of the eyeglasses and a reflection vector, e.g., asdescribed below.

In some demonstrative embodiments, as shown in FIG. 3, a firstreflection vector 317 corresponding to a first tilting angle of theeyeglasses may be different from a second reflection vector 317corresponding to a second tilting angle of the eyeglasses,

In some demonstrative embodiments, the relative angle may be determined,for example, based on two or more images corresponding to two or moretilting angles of the eyeglasses.

In some demonstrative embodiments, while a nominal spherical, acylindrical power and/or a cylindrical axis of lens 320 may remainconstant, a change in magnification and deformation of one or moreelements of object 340 may be different, for example, based on thetilting angle.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to instruct the user to tilt the eyeglasses with respect toat least one axis, and to capture with the camera at least two images,e.g., images 332 and 333, when object 340 is behind lens 320, forexample, while tilting the eyeglasses.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to calculate for the at least two images an estimatedspherical power, cylindrical power and/or a cylindrical axis of lens310, for example, F(D), e.g., as described below.

In some demonstrative embodiments, an algorithm may be configured todetermine one or more optical parameters, denoted D₀, of the lens,and/or a nominal spherical power of the lens, for example, by minimizinga function based on a set of different tilting angles, denoted K, e.g.,as follows:

$\begin{matrix}{\min\limits_{D_{0},\underset{\_}{K}}{{{{\Phi\left( \underset{¯}{K} \right)}{F\left( {\Gamma\underset{¯}{D}} \right)}{\Phi\left( \underset{\_}{K} \right)}} - {F\left( \underset{\_}{D_{0}} \right)}}}_{P}} & (6)\end{matrix}$wherein Γ{ } denotes selection of a set with a minimal correlationoperator, P denotes a Norm order, and F=F(S, C, φ)=F(D).

Reference is made to FIGS. 4A and 4B, which schematically illustrate ameasurement scheme 400, in accordance with some demonstrativeembodiments.

In some demonstrative embodiments, as shown in FIG. 4A, a lens 410 maybe placed in front of a camera 418.

In one example, a flash of the camera may be located right next to apinhole of camera 418.

In some demonstrative embodiments, as shown in FIGS. 4A and 4B, theremay be a relative angle, denoted θ, between a plane 404 of lens 410 anda plane 408 of camera 418.

In some demonstrative embodiments, as shown in FIG. 4A, lens 410 mayhave a first, e.g., curved, surface 416 having a radius R1, and asecond, e.g., flat, surface 417. In one example, surfaces 416 and/or 417may be refractive and reflective surfaces.

In some demonstrative embodiments, a diffractive coefficient, denoted n,of lens 410 may be greater than zero, e.g., n>0.

In some demonstrative embodiments, as shown in FIG. 4A, there may be adistance 415, denoted L, between lens 410 and camera 418.

In some demonstrative embodiments, as shown in FIG. 4B, a firstreflection 401 and a second reflection 402 of a flash on lens 410, maydeviate from a lens center 406 of the lens.

In some demonstrative embodiments, a first magnification, denoted M₁,corresponding to first reflection 401, and a second magnification,denoted M₂, corresponding to second reflection 402, may be determined,e.g., as follows:

$\begin{matrix}{{M_{1} = \frac{1}{\frac{u}{f_{M}} - 1}},{M_{2} = \frac{1}{\frac{u}{f_{L\; 2}} - 1}}} & (7)\end{matrix}$wherein, u is equal to L cos(θ), f_(M) denotes a mirror focal length,and f_(L2) denotes a lens focal length.

In some demonstrative embodiments, the relative angle θ, may bedetermined, for example, based on a first reflection, e.g., reflection401, from a first surface, e.g., surface 416, with respect to the lenscenter 406, e.g., as follows:

$\begin{matrix}{\theta = \frac{\Delta x_{1}*\left( {1 - M_{1}} \right)}{2f_{C}*M_{1}}} & (8)\end{matrix}$wherein Δx₁ denotes a lateral displacement of reflection 401 from lenscenter 406, and fc denotes a focal length of camera 418.

In some demonstrative embodiments, the relative angle θ, may bedetermined, for example, based on a second reflection, e.g., reflection402, from a second surface, e.g., surface 417, with respect to the lenscenter 406, e.g., as follows:

$\begin{matrix}{\theta = \frac{\Delta x_{2}*\left( {1 + M_{2}} \right)}{2f_{C}*M_{2}}} & (9)\end{matrix}$wherein Δx₂ denotes a lateral displacement of reflection 402 from lenscenter 406.

In some demonstrative embodiments, the relative angle θ, may bedetermined, for example, based on the first and second reflections,e.g., reflections 401 and 402, for example, based on a reflectiondistance, denoted Δx, between the first and second reflections, forexample, even without locating a center of the lens, e.g., as follows:

$\begin{matrix}{\theta = \frac{\Delta{x\left( {1 - M_{1}} \right)}\left( {1 + M_{2}} \right)}{2f_{C}*\left( {M_{1} + M_{2}} \right)}} & (10)\end{matrix}$

In some demonstrative embodiments, the reflection vector mayberepresented in a Cartesian axis, for example, by projecting thereflection vector on the X-axis and the Y-axis. For example, a relativeX-axis angle may be determined based on the projection of the reflectionvector on the X-axis, and/or a relative Y-axis angle may be determinedbased on the projection of the reflection vector on the Y-axis.

In one example, the relative X-axis angle may be determined according toEquation 10, for example, based on an X-axis projection of thereflection vector, and/or a relative Y-axis angle may be determinedaccording to Equation 10, for example, based on a Y-axis projection ofthe reflection vector.

In some demonstrative embodiments, the relative angle θ may be used as acorrection factor to correct one or more optical parameters of the lens,for example, by analyzing an aberration created from a tilt of the lens,e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine a correction factor for measured optical parameters of thelens, for example, by analyzing the aberration created from a tilt ofthe lens based on the reflections of the flash on the back surface ofthe lens and/or on a front surface of the lens, e.g., as describedbelow.

In some demonstrative embodiments, the correction factor may be set, forexample, for an estimated spherical power, an estimated cylindricalpower and/or an estimated cylindrical axis of the lens, e.g., tocompensate for a tilt of the lens.

In some demonstrative embodiments, application 160 may determine a powercorrection, denoted F_(NEWSPH), to correct an estimated spherical power,denoted F_(SPH), for example, based on the relative angle θ, e.g., asfollows:

$\begin{matrix}{F_{NEWSPH} = {\left( {1 + \frac{\sin^{2}\theta}{2n}} \right)F_{SPH}}} & (11)\end{matrix}$

In some demonstrative embodiments, application 160 may determine acylinder correction, denoted C_(INDCYL), to correct an estimatedcylindrical power, for example, based on the relative angle θ and thepower correction, e.g., as follows:C _(INDCYL) =F _(NEWSPH)·tan²θ  (12)

Reference is made to FIGS. 5A and 5B, which depict a first image 530 anda second image 550 of eyeglasses, in accordance with some demonstrativeembodiments.

In some demonstrative embodiments, as shown in FIGS. 5A and 5B, image530 and image 550 may include a front reflection 502 and a backreflection 504 of a flash on a right lens 510 of eyeglasses, and a frontreflection 506 and a back reflection 508 of the flash on a left lens 520of the eyeglasses.

In some demonstrative embodiments, two reflections on a lens, e.g.,reflections 502 and 504 on lens 510, may indicate an angle generatedbetween an optical axis of the lens and a camera, which captured theimage.

In some demonstrative embodiments, when the two reflections are visiblebut do not coincide, a distance, horizontally and/or vertically, betweena front reflection and a back reflection may be utilized, for example,to estimate a tilt angle of the lens from an optical axis of the lens,e.g., as described below.

In some demonstrative embodiments, additional information, e.g., a lenspower, a cylinder power and/or a cylindrical axis, may be used, forexample, to analyze the lens tilt with higher precision.

In one example, for a given or calculated approximate power of a lens,device 102 (FIG. 1) may be configured to determine a radius of curvatureof the lens, e.g., as described below.

In another example, for a given or calculated radius of the lens and thedistance of the lens from the camera, application 160 (FIG. 1) may beconfigured to determine an optical axis of the lens, for example, basedon a displacement between the two reflections, e.g., as described below.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to determine a spherical power, a cylindrical power, and/or acylindrical axis of the lens, e.g., as described below.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to determine the cylindrical power, the cylindrical angleand/or the spherical power of the lens, for example, based on the tworeflections, e.g., as described below.

In some demonstrative embodiments, diameters of the front reflection andthe back reflection may be used, for example, to measure the front andback radii of the front and back surfaces, respectively.

For example, for a given or a calculated distance of the camera from thelens and given that the lens surface acts as a mirror, application 160(FIG. 1) may be configured to determine the radius of the mirror or lenssurface, for example, by estimating a magnification of an imagedreflection of the flash.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to determine the power of the lens, for example, based onpositions of the reflections.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to determine the power of the lens for a given tilt angle ofthe eyeglasses, for example, based on the positions of the reflections.

In some demonstrative embodiments, as shown in FIG. 5B, a verticaldisplacement of the front reflection 502 from the back reflection 504 ofleft lens 510, may indicate that the tilt of the lens 510 is around thehorizontal axis.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to determine the tilt angle of the lens for a given orcalculated lens power, for example, based on the positions of thereflections.

In some demonstrative embodiments, sizes of the two reflections may bedirectly related to the radii of the front and back lens surfaces.

In some demonstrative embodiments, the reflections may defer by adiameter size of the reflection, which may indicate a difference betweenthe front surface and the back surface radiuses of curvature of thelens.

In some demonstrative embodiments, as shown in FIG. 5A, a differencebetween the front reflection 502 and the back reflection 504 on leftlens 510 may result, for example, from a difference between a radii ofthe front surface and a radii of the back surface.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to determine the lens power, for example, based on relativespot sizes of the two reflections.

In some demonstrative embodiments, device 102 may be configured todetermine an optical axis of the lens, for example, based on the tworeflections, e.g., as described below.

In some demonstrative embodiments, a point in which the front reflectionand the back reflection from the flash coincide may mark the opticalaxis of the lens, e.g., as described below.

In one example, an on axis object may always be imaged on the opticalaxis of the lens, therefore no matter what different radius ofcurvatures the front surface and the back surface of the lens have, bothimages of the reflections may overlap, e.g., since both reflections areimaged on the optical axis.

Reference is made to FIG. 6, which depicts an image of a frontreflection 602 and a back reflection 604 of a flash on a right lens 610of eyeglasses, and a front reflection 606 and a back reflection 608 ofthe flash on a left lens 620 of the eyeglasses, in accordance with somedemonstrative embodiments.

In some demonstrative embodiments, as shown in FIG. 6, the frontreflection 602 and the back reflection 604 on the left lens 620 maycoincide.

In some demonstrative embodiments, the coinciding of reflections 602 and604 may indicate that the lens plane of lens 610 and the camera planeare parallel.

In some demonstrative embodiments, as shown in FIG. 6, the frontreflection 606 and the back reflection 608 on the right lens 620 almostcoincide, and may indicate a minor angle between the lens plane of lens620 and the camera plane.

Reference is made to FIG. 7, which schematically illustrates areflection scheme 700, in accordance with some demonstrativeembodiments.

In some demonstrative embodiments, as shown in FIG. 7, two imagedreflections 720 of a flash, e.g., a first reflection 701 from a frontsurface 708 of a lens 710 and a second reflection 702 from a backsurface 706 of lens 710, may be captured by a camera sensor 718 of acamera.

In some demonstrative embodiments, as shown in FIG. 7, imagedreflections 720 may not coincide, for example, if the camera is tiltedfrom the optical axis 716 of the lens.

In some demonstrative embodiments, for example, if the lens 710 islocated far enough from the camera, and the flash 722 is close enough tothe lens 710, both reflections 701 and 702 may be imaged on the opticalaxis of the lens and may coincide, e.g., once the lens surface isperpendicular to the device.

Referring back to FIG. 1, in some demonstrative embodiments, application160 may be configured to determine a pupillary distance of theeyeglasses, for example, based on the reflections.

In some demonstrative embodiments, a user of device 102 may beinstructed to perform one or more operations including holding theglasses still, and aiming the flash separately to each lens of theglasses, for example, to enable application 160 to determine thepupillary distance of the eyeglasses.

In some demonstrative embodiments, application 160 may be configured torecord a first position within a first lens of eyeglasses where bothreflections coincide or are calculated to coincide. For example, thefirst position may be recorded relative to a fixed point within theeyeglasses frame.

In some demonstrative embodiments, application 160 may be configured torecord a second position within a second lens of the eyeglasses whereboth reflections coincide or are calculated to coincide. For example,the second position may be recorded relative to the fixed point withinthe eyeglasses frame.

In some demonstrative embodiments, application 160 may be configured todetermine a relative distance between the first position and the secondposition, which may be set as the pupillary distance parameter of theeyeglasses.

Reference is made to FIG. 8, which schematically illustrates a method ofdetermining one or more optical parameters of a lens, in accordance withsome demonstrative embodiments. For example, one or operations of themethod of FIG. 8 may be performed by a system, e.g., system 100 (FIG.1); a computing device, e.g., device 102 (FIG. 1); a server, e.g.,server 170 (FIG. 1); and/or an application, e.g., application 160 (FIG.1).

As indicated at block 802 the method may include capturing an image of alens by a camera using a flash. For example, application 160 (FIG. 1)may instruct the user and/or may trigger capturing the image includingthe at least one reflection of the flash 122 (FIG. 1) on the lens theeyeglasses, e.g., as described above.

As indicated at block 804 the method may include determining one or moreestimated optical parameters of the lens corresponding to a relativeangle between a plane of the lens and a plane of the camera when theimage is captured. For example, application 160 (FIG. 1) may determinethe one or more estimated optical parameters of the lens, for example,based on the comparison between the reference object and the referenceobject image in the captured image, e.g., as described above.

As indicated at block 806 the method may include identifying at leastone reflection of the flash from at least one surface of the lens. Forexample, application 160 (FIG. 1) may identify first reflection 401(FIG. 4) from front surface 416 (FIG. 4) and/or second reflection 402(FIG. 4) from back surface 418 (FIG. 4), e.g., as described above.

As indicated at block 810 the method may include determining therelative angle between the plane of the lens and the plane of thecamera. For example, application 160 (FIG. 1) may determine the relativeangle θ, for example, based on reflections 401 and/or 402 (FIG. 4),e.g., as described above.

As indicated at block 808 determining the relative angle between theplane of the lens and the plane of the camera may include determining acenter of the lens and at least one reflection vector from the center ofthe lens to the at least one reflection, and determining the relativeangle based on the center of the lens, and the reflection vector fromthe center of the lens to the at least one reflection. For example,application 160 (FIG. 1) may determine the relative angle θ, forexample, based on lens center 406 and the reflection vectorcorresponding to reflections 401 and/or 402 (FIG. 4), e.g., as describedabove.

In other embodiments, determining the relative angle between the planeof the lens and the plane of the camera may include determining therelative location of a first reflection relative to a location of asecond reflection, and determining the relative angle based on a vectorbetween the first and second reflections. For example, application 160(FIG. 1) may determine the relative angle θ, for example, based onlocations of reflections 401 and/or 402 (FIG. 4), e.g., as describedabove.

As indicated at block 812 the method may include refining the estimatedoptical parameters of the lens based on the relative angle. For example,application 160 (FIG. 1) may determine the spherical power, thecylindrical power and/or the cylindrical axis of the lens, for example,based on the relative angle θ, e.g., according to Equations 11 and/or12, e.g., as described above.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of the lens, for example,based on the relative angle, e.g., as described above.

In other embodiments, application 160 may be configured to determine theone or more optical parameters of the lens, for example, based on anyother methods, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of the lens, for example,based on a first distance (“the camera distance”) between the object andcamera 118 when the image is captured via the lens, and a seconddistance (“the lens distance”) between the object and the lens of theeyeglasses (“the eyeglasses lens”) when the image is capture via thelens.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of the lens, for example,based on the magnification, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of the lens, for example,based on the first and second distances, e.g., as described below.

In some demonstrative embodiments, the lens distance may be set to be,measured to be, approximated to be, and/or assumed to be, half of thecamera distance, e.g., as described below.

In other embodiments, any other relationship between the first andsecond distances may be set, measured, approximated, and/or assumed,e.g., as described below.

In other embodiments, the first and/or second distances may be setand/or defined based on one or more measurements and/or based on one ormore images captured via the lens, e.g., as described below.

Reference is made to FIG. 9, which schematically illustrates ameasurement scheme 200, in accordance with some demonstrativeembodiments. In one example, one or more elements of FIG. 1 may bearranged and/or operated according to the measurement scheme 200, one ormore parameters may be determined be application 160 (FIG. 1) based onmeasurement scheme 200, and/or one or more measurements may be performedbe one or more elements of FIG. 1 according to measurement scheme 9200,e.g., as described below.

As shown in FIG. 9, measurement scheme 9200 may include a display 9230to display an object, an eyeglasses lens 9210 (“the lens”), a lens 9228(“the camera lens”) of a camera 9218, and/or a sensor 9229 (“the camerasensor”) of the camera 9218. For example, display 9230 may perform thefunctionality of display 130 (FIG. 1), and/or camera 9218 may performthe functionality of camera 118 (FIG. 1).

As shown in FIG. 9, a camera distance, denoted L, may be between display9230 and the camera 9218, e.g., the camera lens 9228; a lens distance,denoted u, may be between the eyeglasses lens 9210 and display 9230;and/or a third distance, denoted v, may be between the camera lens 9228and the camera sensor 9229.

As shown in FIG. 9, the lens 9210 may have a focal length, denoted f₁,and/or the camera lens 9228 may have a focal length, denoted f₂.

In some demonstrative embodiments, the following equations may beapplied, for example, if the lens 9210 includes a negative lens.

In some demonstrative embodiments, positive values for f₁ may be used,for example, if lens 9210 include a negative lens, e.g., as describedbelow.

In some demonstrative embodiments, negative values for f₁, e.g., −f₁,may be used, for example, if lens 9210 includes a positive lens.

In some demonstrative embodiments, according to measurement scheme 9200,one or more relationships may be applied, e.g., as follows:

$\begin{matrix}{{{\frac{1}{u} + \frac{1}{v}} = \frac{1}{f_{1}}}{v = \frac{f_{1}u}{u - f_{1}}}{{M_{1} \equiv \frac{v}{u}} = \frac{f_{1}}{u - f_{1}}}} & (13)\end{matrix}$

In some demonstrative embodiments, sensor 9229 may sense the object onthe display 9230 at a new location, denoted u′, e.g., as follows:

$\begin{matrix}{u^{\prime} = {\frac{{- f_{1}}u}{u - f_{1}} + \left( {L - u} \right)}} & (14)\end{matrix}$

In some demonstrative embodiments, a magnification, denoted M₂, of thecamera lens 9228, may be determined, e.g., as follows:

$\begin{matrix}{M_{2} = {\frac{f_{2}}{u^{\prime} - f_{2}} = \frac{f_{2}}{{\begin{matrix}{{- f_{1}}u} \\{u - f_{1}}\end{matrix} + \left( {L - u} \right) - f_{2}}\;}}} & (15)\end{matrix}$

In some demonstrative embodiments, a total magnification, denoted M_(T),according to the measurement scheme 9200 may be determined, e.g., asfollows:

$\begin{matrix}{M_{T} = {{M_{1}*M_{2}} = {\frac{f_{2}f_{1}}{{{- f_{1}}u} + {\left( {L - u} \right)\left( {u - f_{1}} \right)} - {f_{2}\left( {u - f_{1}} \right)}} = \frac{f_{2}f_{1}}{{Lu} - {Lf}_{1} - u^{2} - {f_{2}\left( {u - f_{1}} \right)}}}}} & (16)\end{matrix}$wherein M₁ denotes a magnification of the lens 210.

In some demonstrative embodiments, the magnification, denoted M₀, at alocation u=0 may be, e.g., as follows:

$\begin{matrix}{M_{0} = \frac{f_{2}}{L - f_{2}}} & (17)\end{matrix}$

In some demonstrative embodiments, the magnification M₀ may be equal toa magnification without the lens 9210.

In some demonstrative embodiments, a relative magnification, denotedM_(R), may be determined, e.g. as follows:

$\begin{matrix}{M_{R} = {\frac{M_{T}}{M_{0}} = \frac{f_{1}\left( {f_{2} - L} \right)}{{L\left( {u - f_{1}} \right)} - u^{2} + {f_{2}f_{1}} - {f_{2}u}}}} & (18)\end{matrix}$

In some demonstrative embodiments, a largest magnification ofmeasurement scheme 9200 may occur at a position, at which the relativemagnification M_(R) satisfies one or more conditions, e.g., as follows:

$\begin{matrix}{{\frac{dM_{R}}{du} = 0}{\frac{dM_{R}}{du} = {{{- \frac{f_{1}\left( {f_{2} - L} \right)}{\left\lbrack {{L\left( {u - f_{1}} \right)} - u^{2} + {f_{2}f_{1}} - {f_{2}u}} \right\rbrack^{2}}}*\left( {L - {2u} - f_{2}} \right)} = 0}}} & (19)\end{matrix}$

In other embodiments, the largest magnification may occur at a position,denoted u_(ideal), which satisfies, e.g., at least the followingcriterion:

$\begin{matrix}{u_{ideal} = \frac{L - f_{2}}{2}} & (20)\end{matrix}$

In some demonstrative embodiments, since L>>f₂ the best position for thelargest magnification may be, e.g., approximately, at a middle betweendisplay 9230 and the camera lens 9228.

In some demonstrative embodiments, the relative magnification M_(R), forexample, at the position u_(ideal), e.g., at the middle between display9230 and the camera lens 9228, may be determined, e.g., as follows:

$\begin{matrix}{{M_{R}\left( {u = u_{ideal}} \right)} \approx \frac{f_{1}\left( {L - f_{2}} \right)}{{L\left( {{{0.5}L} - f_{1}} \right)} - {0.25L^{2}} + {f_{2}f_{1}} - {{0.5}f_{2}L}}} & (21)\end{matrix}$

In some demonstrative embodiments, a spherical power of lens 9210 may beextracted for a given camera distance L, for example, by measuring therelative magnification M_(R), e.g., preferably at the position u_(ideal)peak, or at any other point.

In some demonstrative embodiments, if the lens 9210 has a cylinder, therelative magnification formula, e.g., according to Equation 21, may beapplied to each of the cylinder axes separately.

In some demonstrative embodiments, the distance U between the display9230 and the lens 9210 may be determined, for example, using themagnification formula, e.g., according to Equation 21.

In some demonstrative embodiments, since the maximum magnification isgiven at the middle between display 9230 and lens 9228, capturingseveral images, when the lens 9210 is located at different distancesbetween display 9230 and the camera lens 9228, may enable evaluating themaximum magnification, for example, by fitting, extrapolating orsampling, and/or from a known/calculated/measured camera distance L ofthe camera from the display 9230.

In some demonstrative embodiments, the focal length f₁ of lens 9210 maybe determined, for example, based on the total magnification M_(T),and/or the relative magnification M_(R), e.g., as follows:

$\begin{matrix}{{f_{1} = \frac{{Lu} - u^{2} - {f_{2}u}}{{f_{2}/M_{T}} + L - f_{2}}}{or}{f_{1} = \frac{{Lu} - u^{2} - {f_{2}u}}{{f_{2}/M_{R}} - {L/M_{R}} + L - f_{2}}}} & (22)\end{matrix}$

In some demonstrative embodiments, a focus of the camera 9218 may befixed, for example, on the distance of the camera to display 9230.

In some demonstrative embodiments, the camera 9218 may focus on display9230 and lock the focus, e.g., before inserting the lens 9210 in frontof camera 9218.

In other embodiments, the focusing on display 9230 may be performed, forexample, after placing the lens 9210, e.g., between display 9230 and thecamera 9218, e.g., by focusing on the parts on display 9230 that do notinclude the frame of the eyeglasses, e.g., including the lens 9210, inthe field of view (FOV) of the camera 9218. For example, imageprocessing techniques may be implemented to determine where in the FOVshould the camera 9218 perform the autofocus (AF).

In another embodiment, the area in the FOV of the camera 9218 to performthe AF may be selected manually, for example, by instructing the user toselect the area in the FOV of the camera 9218, in which the camera mayfocus.

In some demonstrative embodiments, the magnification and the extractionof the focal power of lens 9210 may be determined, for example, byfocusing only on display 9230.

In some demonstrative embodiments, camera 9218 may be focused using theobject on display 9230, for example, without the lens 9210, e.g., asfollows:

$\begin{matrix}{v_{s} = \frac{{Lf}_{2}}{L - f_{2}}} & (23)\end{matrix}$

In some demonstrative embodiments, the lens 9210 may form a virtualobject located at the distance u′ from camera lens, e.g., as follows:

$\begin{matrix}{u^{\prime} = {L - u + \frac{f_{1}u}{f_{1} + u}}} & (24)\end{matrix}$

In some demonstrative embodiments, the total magnification M_(T) in thesystem may be determined, e.g., as follows:

$\begin{matrix}{M_{T} = {{M_{1}M_{2}} = {\frac{f_{1}}{f_{1} + u} \times \frac{\frac{Lf_{2}}{L - f_{2}}}{L - u + \frac{f_{1}u}{f_{1} + u}}}}} & (25)\end{matrix}$

In some demonstrative embodiments, the focal length f₁ of the lens 9210may be determined, e.g., as follows:

$\begin{matrix}{f_{1} = \frac{\left( {L - u} \right)M_{T}u}{\frac{{Lf}_{2}}{L - f_{2}} - {LM}_{T}}} & (26)\end{matrix}$

In some demonstrative embodiments, the power, denoted P₁, of the lens9210 may be determined, e.g., as follows:

$\begin{matrix}{P_{1} = \frac{1}{f_{1}}} & (27)\end{matrix}$

Reference is made to FIG. 10, which schematically illustrates an image9300 of an object 9302 displayed on a display 9330. For example, display9330 may perform the functionality of display 130 (FIG. 1).

In some demonstrative embodiments, as shown in FIG. 10, object 9302 mayinclude a circle.

In some demonstrative embodiments, image 9300 of object 9302 may becaptured by a camera via a lens 9310. For example, camera 118 (FIG. 1)and/or camera 9218 (FIG. 9) may capture object 9302 via lens 9310, e.g.,lens 9210 (FIG. 9).

As shown in FIG. 10, when image 9300 of object 9302 is captured throughlens 9310, lens 9310 may change the magnification of object 9302, e.g.,in a different way for various angles.

As shown in FIG. 10, when an image of object 9302 is captured throughlens 9310, image 9300 may be seen as an ellipsoid.

In some demonstrative embodiments, the camera may be focused to acalibration object 9301, which may be placed outside of the field ofview of lens 9310.

In some demonstrative embodiments, as shown in FIG. 10, lens 9310 maynot affect an image of the calibration object 9301, e.g., sincecalibration object 9301 is placed outside of the FOV of lens 9310.

Reference is made to FIGS. 11A, 11B, and 11C and 11D which schematicallyillustrate four respective relative magnification graphs, in accordancewith some demonstrative embodiments.

In one example, the camera distance L, e.g., between camera 9218 (FIG.9) and display 230 (FIG. 9), may be equal to 50 cm, and the focal lengthf₂, e.g., of lens 228 (FIG. 9), may be equal to 3.7 mm. In otherembodiments, any other distances may be used.

In some demonstrative embodiments, the four graphs of FIGS. 11A, 11B,and 11C and 11D depict the relative magnification as a function of adistance of a lens, e.g., lens 9210 (FIG. 9), from a camera sensor,e.g., sensor 9229 (FIG. 9).

In some demonstrative embodiments, a graph of FIGS. 11A, 11B, and 11Cand 11D depicts a plurality of magnification curves corresponding to aplurality of different lenses.

In some demonstrative embodiments, the plurality of different lenses maycorrespond to a plurality of diopter intervals within a certain range ofdiopters.

For example, a magnification curve may represent a magnification of alens having a specific diopter from the certain range of diopters as afunction of the distance of the lens from the camera.

In some demonstrative embodiments, the plurality of magnification curvesof FIG. 11A may correspond to a plurality of lenses having a lens powerof between 0.25D and 2D, at 0.25 diopter intervals.

In some demonstrative embodiments, the plurality of magnification curvesof FIG. 11B may correspond to a plurality of lenses having a lens powerof between 2D and 4D, at 0.25 diopter intervals.

In some demonstrative embodiments, the plurality of magnification curvesof FIG. 11C may correspond to a plurality of lenses having a lens powerof between −0.25D and −2D, at 0.25 diopter intervals.

In some demonstrative embodiments, the plurality of magnification curvesof FIG. 11D may correspond to a plurality of lenses having a lens powerof between −2D and −4D, at 0.25 diopter intervals.

In other embodiments, any other curves may be used with respect to anyother diopter ranges and/or any other diopter intervals.

In one example, a lens may have a lens power of −4 diopters. Accordingto this example, it may be expected that the lens may have a maximalrelative magnification of 1.5.

In another example, a lens may have a lens power of −4D with a cylinderpower of +0.25D. According to this example, it may be expected that thelens may have a maximal relative magnification of 1.5 at a first axis,and a relative magnification of 1.47 at a second axis.

As shown in FIGS. 11A, 11B, and 11C and 11D, a change of few percent inmagnification may be expected for a lens of 0.25 diopter.

In one example, a centimeter size object on the display 9230 (FIG. 10)may occupy a few hundreds of pixels on the camera sensor. Accordingly, achange of a few percent in a size of the object may result in a changeof a few pixels, which may be traceable.

Referring back to FIG. 1, in some demonstrative embodiments, one or moreprocedures, operations, and/or methods may be performed to measure theone or more optical parameters of the lens, e.g., as described below.

In some demonstrative embodiments, the one or more operations mayinclude placing the lens of the eyeglasses between camera 118 anddisplay 180.

In some demonstrative embodiments, parameters as a lens power, a lenscylindrical power, a lens cylinder angle, and/or any other parameters ofthe eyeglasses lens may be determined, for example, by tracking thechange of the image captured by camera 118 via the lens.

In some demonstrative embodiments, determining the one or more opticalparameters of the lens may be based for example, on the camera distance,e.g., between the object, which is displayed on display 130, and camera118; the lens distance, e.g., between the object and the lens; and/or adetected change in the image, e.g., as described below.

In some demonstrative embodiments, application 160 may utilize the oneor more operations to determine the one or more optical parameters ofthe lens, for example, based on a magnification between an imageddimension of the object and a respective reference dimension of theobject, which may be displayed on display 130, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine a spherical power of the lens based on the magnification,e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine a cylindrical axis of the lens, for example, based on amaximal magnification axis of a plurality of axes in the image, at whicha magnification between the imaged dimension and the reference dimensionis maximal, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the cylindrical power of the lens, for example, based on themaximal magnification axis, and a minimal magnification axis of theplurality of axes in the image, at which a magnification between anotherimaged dimension and another respective reference dimension of theobject is minimal, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the cylindrical power of the lens, for example, based on afirst magnification at the minimal magnification axis, and a secondmagnification at the maximal magnification axis, e.g., as describedbelow.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of the lens, for example,based on an extremum magnification image, e.g., a maximal or minimalmagnification image, which may be selected from a plurality ofmagnification images, e.g., as described below.

In some demonstrative embodiments, the extremum magnification image ofthe plurality of images, may include an image in which a magnificationbetween the imaged dimension and the reference dimension is maximal orminimal.

In some demonstrative embodiments, application 160 may be configured toprocess a plurality of images of the object captured via the lens at arespective plurality of camera distances, e.g., between the camera andthe object, while the lens distance is constant. For example,application 160 may be configured to instruct the user of the eyeglassesto move camera 118 backward and/or forward from display 130, while theeyeglasses remain static with respect to display 130.

In some demonstrative embodiments, application 160 may be configured todetermine an extremum magnification image of the plurality of images,which may have an extremum magnification between the imaged dimensionand the reference dimension.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of the lens, for example,based on the extremum magnification image, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured toprocess a plurality of images of the object captured via the lens at arespective plurality of lens distances, e.g., between the lens and theobject, while the camera distance is constant. For example, application160 may be configured to instruct the user eyeglasses to move theeyeglasses backward and/or forward between camera 118 and display 130,while the camera 118 remains static with respect to display 130.

In some demonstrative embodiments, application 160 may be configured todetermine an extremum magnification image of the plurality of images,which provides n extremum of the magnification between the imageddimension and the reference dimension.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of the lens, for example,based on the extremum magnification image, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of the lens, for example,based on the magnification, and another magnification of at least onedimension in an image of a calibration object having known dimensions,e.g., calibration object 9301 (FIG. 10).

In some demonstrative embodiments, the image of the calibration objectmay be captured not via the lens, e.g., as described above withreference to FIG. 10.

In some demonstrative embodiments, application 160 may be configured todetermine the first distance, e.g., between the object and camera 118,and/or the second distance, e.g., between the object and the lens, basedon one or more distance measurements, estimations, and/or calculations,e.g., as described below.

In some demonstrative embodiments, the first distance and/or the seconddistance may be predefined, e.g., as described below.

In some demonstrative embodiments, the second distance may be set toinclude a distance between the object and the lens when temple arms ofthe eyeglasses are extended to a plane of the object.

In some demonstrative embodiments, application 160 may be configured todetermine the first distance and/or the second distance, for example,based on acceleration information corresponding to an acceleration ofcamera 118 and/or device 102, e.g., when one or more images are capturedby camera 118.

In some demonstrative embodiments, device 102 may include anaccelerometer 126 configured to provide to application 160 theacceleration information of camera 118 and/or device 102.

In some demonstrative embodiments, application 160 may be configured todetermine the first distance and/or the second distance, for example,based on one or more three-dimensional (3D) coordinates of the object.

In some demonstrative embodiments, device 102 may include a 3D sensorconfigured to determine one or more three-dimensional (3D) coordinatesof an object.

In some demonstrative embodiments, application 160 may be configured todetermine the first distance, for example, based on the object and atleast one dimension in the image of a calibration object having knowndimensions, e.g., calibration object 301 (FIG. 10).

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of the lens, for example,according to one or more operations, e.g., as described below.

Reference is made to FIG. 12, which schematically illustrates a methodof determining one or more optical parameters of a lens, in accordancewith some demonstrative embodiments. For example, one or operations ofthe method of FIG. 12 may be performed by a system, e.g., system 100(FIG. 1); a mobile device, e.g., device 102 (FIG. 1); a server, e.g.,server 170 (FIG. 1); a display, e.g., display 130 (FIG. 1); and/or anapplication, e.g., application 160 (FIG. 1).

As indicated at block 9502, the method may include displaying an objecton a display. For example, application 160 (FIG. 1) may cause display130 (FIG. 1) to display the object, e.g., as described above.

As indicated at block 9504, the method may include placing an eyeglasseslens (also referred to as “Lens Under Test (LUT)) at a certain distancefrom the display. For example, application 160 (FIG. 1) may instruct theuser to place the lens at the lens distance from the display 130 (FIG.1), e.g., as described above.

As indicated at block 9506, the method may include capturing with acamera through the eyeglasses lens an image of the object displayed onthe display. For example, application 160 (FIG. 1) may cause camera 118(FIG. 1) to capture the image of the object, for example, via the lens,e.g., as described above.

As indicated at block 9508, the method may include determining a firstdistance of the camera from the display, e.g., the camera distance, anda second distance of the eyeglasses lens from the display, e.g., thelens distance. For example, application 160 (FIG. 1) may determine thelens distance and the camera distance, e.g., as described above.

In some demonstrative embodiments, the camera distance and/or the lensdistance may be estimated, given and/or advised to the user.

As indicated at block 9510, the method may include estimating a maximalmagnification of the object for a certain meridian, e.g., as describedbelow with respect to an exemplary object. For example, application 160(FIG. 1) may estimate a magnification of the object for the certainmeridian, e.g., as described above.

As indicated at block 9512, the method may include calculating a focalpower of the lens for the certain meridian. For example, application 160(FIG. 1) may determine a focal power of the eyeglasses lens for thecorresponding axis, e.g., as described above.

As indicated at block 9514, if the magnification varies for variousmeridians, the method may include, locating the minimum magnificationand a corresponding meridian and calculating its focal power. Forexample, application 160 (FIG. 1) may determine that the magnificationvaries for a few meridians and, accordingly application 160 (FIG. 1) maythe minimal magnification axis and the magnification of the minimalmagnification axis, e.g., as described below.

As indicated at block 9516, the method may include determining thecylindrical power as the difference between the two focal powers and theangle of the cylinder. For example, application 160 (FIG. 1) maydetermine the cylindrical power of the lens, for example, based on thefirst magnification at the minimal magnification axis, and the secondmagnification at the maximal magnification axis, e.g., as describedbelow.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured implement one or more techniques to perform the operation ofblock 508, e.g., to determine the camera distance and/or the lensdistance.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to perform one or more operations to determine the cameradistance and/or the lens distance, e.g., as described below.

In some demonstrative embodiments, determining the camera distanceand/or the lens distance may include displaying a calibration objecthaving a known size on the display, capturing an image of the displaywith the camera, and evaluating the distance based on the captured imageof the calibration object.

In some demonstrative embodiments, determining the camera distanceand/or the lens distance may include measuring the distance from thecamera to the display with a reference known size object, e.g., such asa Letter, an A4 paper, a meter, and/or the like.

In some demonstrative embodiments, determining the camera distanceand/or the lens distance may include measuring the displacement of thecamera from the display, for example, by integrating accelerometer data,e.g., from the accelerometer 126 (FIG. 1).

In some demonstrative embodiments, determining the camera distanceand/or the lens distance may include using a 3D sensor or a depthcamera, for example, to determine the camera distance and/or the lensdistance.

Referring back to FIG. 1, in some demonstrative embodiments, application160 (FIG. 1) may be configured to determine the optical parameters ofthe lens based on one or measurement schemes, e.g., as described below.

In some demonstrative embodiments, a first measurement scheme mayinclude placing the lens at the middle between the camera 118 and thedisplay 130, for example, such that the lens distance is approximatelyhalf of the camera distance, e.g., as described below.

In some demonstrative embodiments, a second measurement scheme mayinclude placing the eyeglasses with temple arms extended against thedisplay 130, for example, to locate the eyeglasses at a predefined roughdistance, for example, such that the lens distance is based on thelength of the arm temples, for example, about 14.5 cm, e.g., asdescribed below.

In some demonstrative embodiments, a third measurement scheme mayinclude keeping the camera 118 at a relatively fixed distance from thedisplay 130 and capturing images through the lens, while moving the lensfrom the camera 118 towards the display 130 and/or backwards fromdisplay 130 to the camera 118.

In some demonstrative embodiments, the lens distance may be determinedto be approximately half of the camera distance, for example, at alocation, at which an image captured via the lens has a maximum relativemagnification, e.g., as described below.

In some demonstrative embodiments, a fourth measurement scheme mayinclude placing the eyeglasses lens at a certain distance from thedisplay, and capturing a few images by the camera while changing thecamera position, for example, to determine the location, at which animage captured via the lens has maximum relative magnification, e.g., asdescribed below.

In some demonstrative embodiments, a fifth measurement scheme mayinclude placing the frame of the eyeglasses at a certain distance fromthe display, capturing an image through the lens where the camera islocated at a distance from the lens, and determining the lens distancefrom a size of the frame of the eyeglasses in an image captured by thecamera, e.g., as described below.

In some demonstrative embodiments, a sixth measurement scheme mayinclude placing the eyeglasses at a known distance from the display, forexample, by extending the temple arms, or by using any other method todetermine a known distance, and placing the camera at another knowndistance to capture an image through the lens.

In some demonstrative embodiments, according to the sixth measurementscheme the lens distance may be known, and the camera distance may becalculated, for example, based on a known size image displayed on thedisplay 130 and the camera parameters, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured toperform one or more operations to estimate the camera distance, the lensdistance and/or the one or more optical parameters of the lens, forexample, according to the first measurement scheme, e.g., as describedbelow.

Reference is made to FIG. 13, which schematically illustrates ameasurement scheme 9600, in accordance with some demonstrativeembodiments. For example, one or operations using the measurement scheme9600 may be performed by a system, e.g., system 100 (FIG. 1); a mobiledevice, e.g., device 102 (FIG. 1); a server, e.g., server 170 (FIG. 1);a display, e.g., display 130 (FIG. 1); and/or an application, e.g.,application 160 (FIG. 1).

In some demonstrative embodiments, measurement scheme 9600 may beconfigured to enable to determine one or more optical parameters of alens 9610, for example, according to the first measurement scheme.

In some demonstrative embodiments, as shown in FIG. 13, an imagecapturing device 9602, may be placed at a known distance, denoted L,e.g., the camera distance, from a display 9630. For example, device 9602may perform the functionality of camera 118 (FIG. 1); and/or display9630 may perform the functionality of display 130 (FIG. 1).

In some demonstrative embodiments, the camera distance L may be verifiedby the user and/or may be calculated based on an image of a calibrationobject, and one or more parameters of the camera, e.g., a focal length,a field of view, and/or a sensor pitch.

In some demonstrative embodiments, as shown in FIG. 13, the lens may beplaced approximately midway between the device 9602 and the display9630, e.g., at a distance, denoted 0.5L.

In some demonstrative embodiments, since a sensitivity to thepositioning of the lens at the center is low, accurate estimation of theone or more optical parameters of the lens may be achieved. Positioningthe lens, e.g., even within few centimeters from the middle between thecamera and the display, may still enable to determine the one or moreoptical parameters of the lens as if the lens was positioned exactly inthe middle between the camera and the display.

Reference is made to FIG. 14, which schematically illustrates a methodof determining one or more optical parameters of a lens, in accordancewith some demonstrative embodiments. For example, one or operations ofthe method of FIG. 14 may be performed by a system, e.g., system 100(FIG. 1); a mobile device, e.g., device 102 (FIG. 1); a server, e.g.,server 170 (FIG. 1); a display, e.g., display 130 (FIG. 1); and/or anapplication, e.g., application 160 (FIG. 1).

In some demonstrative embodiments, one or more operations of the methodof FIG. 14 may be performed, for example, using the first measurementscheme, e.g., measurement scheme 9600 (FIG. 13).

As indicated at block 9704, the method may include displaying an objecton a display. For example, application 160 (FIG. 1) may cause display130 (FIG. 1) to display the object, e.g., as described above.

As indicated at block 9702, the method may optionally includecalibrating the display, e.g., as described below.

As indicated at block 9706, the method may include placing a cameradevice at a known or estimated distance from the display. For example,application 160 (FIG. 1) may instruct the user to place camera 118(FIG. 1) at a certain distance from the display 130 (FIG. 1), e.g., asdescribed above with reference to FIG. 13.

As indicated at block 9708, the method may include placing a lensroughly midway between the display and camera. For example, application160 (FIG. 1) may instruct the user to place the lens at the middlebetween camera 118 (FIG. 1) and display 130 (FIG. 1), e.g., as describedabove with reference to FIG. 13.

As indicated at block 9710, the method may include capturing an image ofthe displayed image through the lens. For example, application 160(FIG. 1) may cause camera 118 (FIG. 1) to capture the image of theobject, for example, via the lens, e.g., as described above.

As indicated at block 9712, the method may include analyzing thecaptured image, and determining the power and cylinder of the lens. Forexample, application 160 (FIG. 1) may determine the one or more opticalparameters of the lens, for example, based on the captured image, e.g.,as described above.

Referring back to FIG. 1, in some demonstrative embodiments, application160 may be configured to perform one or more operations to estimate thecamera distance, the lens distance and/or the one or more opticalparameters of the lens, for example, according to the second measurementscheme, e.g., as described below.

Reference is made to FIG. 15, which schematically illustrates ameasurement scheme 9800, in accordance with some demonstrativeembodiments. For example, one or operations of using the measurementscheme 9800 may be performed by a system, e.g., system 100 (FIG. 1); amobile device, e.g., device 102 (FIG. 1); a server, e.g., server 170(FIG. 1); a display, e.g., display 130 (FIG. 1); and/or an application,e.g., application 160 (FIG. 1).

In some demonstrative embodiments, measurement scheme 9800 may beconfigured to enable to determine one or more optical parameters of alens 9810, for example, according to the second measurement scheme.

In some demonstrative embodiments, as shown in FIG. 15, a lens 9810 maybe placed at a known distance, denoted L, from a display 9830. Forexample, display 830 may perform the functionality of display 130 (FIG.1).

In some demonstrative embodiments, as shown in FIG. 14, lens 9810 may beplaced at the distance L by completely extending the temple arms of theeyeglasses and allowing them to touch the display 9830.

In some demonstrative embodiments, since the temple arm is of fixedlength, e.g., of typically 13.5 cm to 15 cm, the distance between thelens and the display may be well defined.

In some demonstrative embodiments, as shown in FIG. 15, an imagecapturing device 9802, may be placed at a distance, denoted 2L, fromdisplay 9830, e.g., a distance approximately equal to twice the lengthof the temple arm. For example, device 9802 may perform thefunctionality of camera 118 (FIG. 1).

In some demonstrative embodiments, the one or more optical parameters ofthe lens may be determined, for example, by capturing an image of theobject from the distance 2L.

Reference is made to FIG. 16, which schematically illustrates a methodof determining one or more optical parameters of a lens, in accordancewith some demonstrative embodiments. For example, one or operations ofthe method of FIG. 16 may be performed by a system, e.g., system 100(FIG. 1); a mobile device, e.g., device 102 (FIG. 1); a server, e.g.,server 170 (FIG. 1); a display, e.g., display 130 (FIG. 1); and/or anapplication, e.g., application 160 (FIG. 1).

In some demonstrative embodiments, one or more operations of the methodof FIG. 16 may be performed, for example, in accordance with the secondmeasurement scheme, e.g., measurement scheme 9800 (FIG. 15).

As indicated at block 9902, the method may optionally includecalibrating a screen to find a pixel/mm ratio. For example, application160 (FIG. 1) may be configured to calibrate display 130 (FIG. 1), e.g.,as described below.

As indicated at block 9904, the method may include extending theeyeglasses temple arms and placing them against the display. Forexample, application 160 (FIG. 1) may instruct the user to extend theeyeglasses temple arms and to place them against the display 130 (FIG.1), e.g., as described above.

As indicated at block 9906, the method may include placing a cameradevice at a known or estimated distance from the display, e.g.,approximately twice the length of the temple arm. For example,application 160 (FIG. 1) may instruct the user to place camera 118(FIG. 1) at a known or estimated distance from display 130 (FIG. 1),e.g., as described above.

As indicated at block 9908, the method may include capturing an imagethrough lens. For example, application 160 (FIG. 1) may cause camera 118(FIG. 1) to capture the image of the object, for example, via the lens,e.g., as described above.

As indicated at block 9910, the method may include determining lenspower and cylinder power and cylinder axis. For example, application 160(FIG. 1) may determine the one or more optical parameters of the lens,for example, based on the captured image, e.g., as described above.

Referring back to FIG. 1, in some demonstrative embodiments, application160 may be configured to perform one or more operations to estimate thecamera distance, the lens distance and/or the one or more opticalparameters of the lens, for example, according to the third measurementscheme, e.g., as described below.

Reference is made to FIG. 17, which schematically illustrates ameasurement scheme 91100, in accordance with some demonstrativeembodiments. For example, one or operations using of the measurementscheme 91000 may be performed by a system, e.g., system 100 (FIG. 1); amobile device, e.g., device 102 (FIG. 1); a server, e.g., server 170(FIG. 1); a display, e.g., display 130 (FIG. 1); and/or an application,e.g., application 160 (FIG. 1).

In some demonstrative embodiments, measurement scheme 91000 may beconfigured to enable to determine one or more optical parameters of alens 91010, for example, according to the third measurement scheme.

In some demonstrative embodiments, as shown in FIG. 17, an imagecapturing device 91002, may be placed at a certain distance, denoted L,e.g., the camera distance, from a display 91030. For example, device91002 may perform the functionality of camera 118 (FIG. 1); and/ordisplay 91030 may perform the functionality of display 130 (FIG. 1).

In some demonstrative embodiments, as shown in FIG. 17, the lens 91010may be moved between the device 91002 and the display 91030, forexample, in order to find the maximal relative magnification.

In some demonstrative embodiments, according to measurement scheme 91000the position of the lens may not need to be monitored.

Reference is made to FIG. 18, which schematically illustrates a methodof determining one or more optical parameters of a lens, in accordancewith some demonstrative embodiments. For example, one or operations ofthe method of FIG. 18 may be performed by a system, e.g., system 100(FIG. 1); a mobile device, e.g., device 102 (FIG. 1); a server, e.g.,server 170 (FIG. 1); a display, e.g., display 130 (FIG. 1); and/or anapplication, e.g., application 160 (FIG. 1).

In some demonstrative embodiments, one or more operations of the methodof FIG. 18 may be performed, for example, in accordance with the thirdmeasurement scheme, e.g., measurement scheme 91000 (FIG. 18).

As indicated at block 91102, the method may optionally includecalibrating a screen to find a pixel/mm ratio. For example, application160 (FIG. 1) may be configured to calibrate display 130 (FIG. 1), e.g.,as described below.

As indicated at block 91104, the method may include displaying an objecton the display. For example, application 160 (FIG. 1) may cause display130 (FIG. 1) to display the object, e.g., as described above.

As indicated at block 91106, the method may include holding a cameradevice at a certain distance from the display. For example, application160 (FIG. 1) may instruct the user to place camera 118 (FIG. 1) at acertain distance from the display 130 (FIG. 1), e.g., as describedabove.

In some demonstrative embodiments, the method may include calculatingthe camera distance. For example, application 160 (FIG. 1) may determinethe camera distance, e.g., as described above.

As indicated at block 91108, the method may include placing a lens closeto the camera 118. For example, application 160 (FIG. 1) may instructthe user to place the lens close to camera 118 (FIG. 1), e.g., asdescribed above.

As indicated at block 91110, the method may include capturing a seriesof images while moving the lens towards the display. For example,application 160 (FIG. 1) may cause camera 118 (FIG. 1) to capture aseries of images while moving the lens towards the display 130 (FIG. 1),e.g., as described above.

In other embodiments, the lens may be moved away from the display andtowards the camera. For example, the lens may be placed close to thedisplay, and a series of images may be captured while moving the lenstowards the camera.

In some demonstrative embodiments, a first option or a second option maybe used to determine when to stop the moving of the lens towards thedisplay.

In some demonstrative embodiments, the first option may include stoppingwhen the lens is very close to the display.

In some demonstrative embodiments, the second option may includecalculating a relative magnification for an arbitrary axis, and stoppingthe movement after the magnification reaches its peak.

As indicated at block 91112, the method may include determining theimage with the maximal magnification, and checking for cylindricaldistortion. For example, application 160 (FIG. 1) may determine thecylindrical axis, for example, based on the maximal magnification of theobject for the certain meridian, e.g., as described below.

In one example, when a circular object is used, an ellipse shape may beseen.

As indicated at block 91116, the method may include calculating the lenspower and the cylindrical power, based on the relative magnification ineach axes and the distance. For example, application 160 (FIG. 1) maydetermine the focal power and the cylindrical power of the eyeglasseslens, for example, based on the magnifications in each axes, e.g., asdescribed above.

In some demonstrative embodiments, the method may optionally includechecking for consistency of the cylindrical distortion at the rest ofthe captured images.

In one example, the consistency of the cylindrical distortion mayindicate an unintended rotation during movement.

Referring back to FIG. 1, in some demonstrative embodiments, application160 may be configured to perform one or more operations to estimate thecamera distance, the lens distance and/or the one or more opticalparameters of the lens, for example, according to the fourth measurementscheme, e.g., as described below.

Reference is made to FIG. 19, which schematically illustrates ameasurement scheme 91200, in accordance with some demonstrativeembodiments. For example, one or operations using of the measurementscheme 91200 may be performed by a system, e.g., system 100 (FIG. 1); amobile device, e.g., device 102 (FIG. 1); a server, e.g., server 170(FIG. 1); a display, e.g., display 130 (FIG. 1); and/or an application,e.g., application 160 (FIG. 1).

In some demonstrative embodiments, measurement scheme 91200 may beconfigured to determine one or more optical parameters of a lens 91210,for example, according to the fourth measurement scheme.

In some demonstrative embodiments, as shown in FIG. 19, the lens may beplaced at a certain distance, denoted L, e.g., the lens distance, from adisplay 91230. For example, or display 91230 may perform thefunctionality of display 130 (FIG. 1).

In some demonstrative embodiments, as shown in FIG. 9, an imagecapturing device 91202 may be placed close to lens 91210. For example,device 91002 may perform the functionality of camera 118 (FIG. 1).

In some demonstrative embodiments, as shown in FIG. 19, the device 91202may be moved away from lens 91210 up to a distance, denoted 2L, e.g.,the camera distance, for example, in order to find the maximal relativemagnification.

In other embodiments, the device 91202 may be placed at approximatelythe distance 2L from the display and moved towards lens 91210, e.g.,while capturing a series of images of the displayed object via the lens91210.

In some demonstrative embodiments, if several images are captured, aselected image, e.g., the image with maximal relative magnification, maybe used to determine one or more of, e.g., all, the optical parametersof lens 91210, for example, by determining the camera distance, forexample, from a known size object captured at the selected image, anddetermining the lens distance as half of the camera-display distance.

Reference is made to FIG. 20, which schematically illustrates a methodof determining one or more optical parameters of a lens, in accordancewith some demonstrative embodiments. For example, one or operations ofthe method of FIG. 20 may be performed by a system, e.g., system 100(FIG. 1); a mobile device, e.g., device 102 (FIG. 1); a server, e.g.,server 170 (FIG. 1); a display, e.g., display 130 (FIG. 1); and/or anapplication, e.g., application 160 (FIG. 1).

In some demonstrative embodiments, one or more operations of the methodof FIG. 20 may be performed, for example, in accordance with the fourthmeasurement scheme, e.g., measurement scheme 91200 (FIG. 19).

As indicated at block 91302, the method may optionally includecalibrating a screen to find a pixel/mm relationship. For example,application 160 (FIG. 1) may be configured to calibrate display 130(FIG. 1), e.g., as described below.

As indicated at block 91304, method may include displaying an object onthe display. For example, application 160 (FIG. 1) may cause display 130(FIG. 1) to display the object, e.g., as described above.

As indicated at block 91306, the method may include holding camera 118at a certain distance from the display. For example, application 160(FIG. 1) may instruct the user to place camera 118 (FIG. 1) at a certaindistance, denoted D, from the display 130 (FIG. 1), e.g., as describedabove.

As indicated at block 91308, the method may include calculating thecamera distance. For example, application 160 (FIG. 1) may determine thecamera distance, e.g., as described above.

As indicated at block 91310, the method may include placing the lens atthe same distance as the device. For example, application 160 (FIG. 1)may instruct the user to place the lens close to camera 118 (FIG. 1),e.g., as described above.

As indicated at block 91312, the method may include moving camera 118backwards up to a distance 2D. For example, application 160 (FIG. 1) mayinstruct the user to move camera 118 (FIG. 1) to the distance 2D, e.g.,as described above.

As indicated at block 91314, the method may include capturing an imageof the object through the lens. For example, application 160 (FIG. 1)may cause camera 118 (FIG. 1) to capture an image via the lens, e.g., asdescribed above.

As indicated at block 91316, the method may include determining theimage with the maximal magnification, and checking for cylindricaldistortion at the object. For example, application 160 (FIG. 1) maydetermine the maximal magnification of the object for the certainmeridian, e.g., as described above.

In one example, for a circular object an ellipse shape may be seen,e.g., as described below.

As indicated at block 91318, the method may include determining acylinder angle from the image distortion. For example, application 160(FIG. 1) may determine the cylindrical axis, for example, based on themaximal magnification of the object for the certain meridian, e.g., asdescribed above.

As indicated at block 91320, the method may include, e.g., for each ofthe axes, determining the relative magnification, and calculating lenspower. For example, application 160 (FIG. 1) may determine the focalpower and the cylindrical power of the eyeglasses lens, for example,based on the magnifications in each axes, e.g., as described above.

Referring back to FIG. 1, in some demonstrative embodiments, application160 may be configured to perform one or more operations to estimate thecamera distance, the lens distance and/or the one or more opticalparameters of the lens, for example, according to the fifth measurementscheme, e.g., as described below.

Reference is made to FIG. 21, which schematically illustrates ameasurement scheme 91400, in accordance with some demonstrativeembodiments. For example, one or more operations using of themeasurement scheme 91400 may be performed by a system, e.g., system 100(FIG. 1); a mobile device, e.g., device 102 (FIG. 1); a server, e.g.,server 170 (FIG. 1); a display, e.g., display 130 (FIG. 1); and/or anapplication, e.g., application 160 (FIG. 1).

In some demonstrative embodiments, measurement scheme 91400 may beconfigured to determine one or more optical parameters of a lens 91410,for example, according to the fifth measurement scheme.

In some demonstrative embodiments, as shown in FIG. 21, an imagecapturing device 91402, may be placed at a certain distance, denoted L2,e.g., the camera distance, from a display 91430. For example, device91402 may perform the functionality of camera 118 (FIG. 1); and/ordisplay 91430 may perform the functionality of display 130 (FIG. 1).

In some demonstrative embodiments, as shown in FIG. 21, the lens 91420may be placed at a distance, denoted L1, e.g., the lens distance,between lens 91420 and display 91430.

In some demonstrative embodiments, as shown in FIG. 21, the device 91402may capture through the lens 91410 an image of an object displayed ondisplay 91430.

In some demonstrative embodiments, the camera distance L2, and/or thelens distance L1 may be arbitrary.

In some demonstrative embodiments, an absolute feature of a frameincluding the lens 91410 or the frame distance from the display may beconsidered as known or calibrated.

In some demonstrative embodiments, for a known or calibrated frame size,or any other feature within the frame (“the calibration object”), thelens distance and the camera distance may be estimated, e.g., asdescribed below.

In some demonstrative embodiments, the calibration object may have aheight, denoted h, which may be known and/or given.

In some demonstrative embodiments, the known object height h may beconsidered as a known or calibrated feature of the frame, for example,the height of the lens, the width of the frame, the bridge length,and/or any other part of the eyeglasses.

In some demonstrative embodiments, a feature size of an element of theframe may also be given, for example, from a query to a database of aspecified frame model, and/or may be specified by a user of device 102(FIG. 1).

In some demonstrative embodiments, an image of the calibration object(“the calibration image”), e.g., when captured via the lens, may have animaged height, denoted h′.

In some demonstrative embodiments, a distance, denoted u, between thelens and the calibration object may be determined, for example, based onthe EFL of the lens, which may be known and/or given, the height h,and/or the imaged height h′, e.g., as described below.

In some demonstrative embodiments, the following Equation may be given,for example, based on triangles similarity, e.g., as follows:

$\begin{matrix}{\frac{h^{\prime}}{h} = {\frac{v}{u} \cong \frac{efl}{u}}} & (28)\end{matrix}$wherein v is approximately the EFL of the lens.

In some demonstrative embodiments, the imaged height h′ of thecalibration image may be based on a number of pixels, denotedh′_pixels_estimated, occupied by the calibration image, and a sensorpitch, denoted pitch, of the lens, e.g., as follows:h′=pitch*h′_pixels_estimated  (29)

In some demonstrative embodiments, the distance u may be determined, forexample, based on Equation 28 and Equation 29, e.g., as follows:

$\begin{matrix}{{u \cong \frac{{efl}*h}{h^{\prime}}} = {\frac{efl}{pitch}*\frac{h}{h^{\prime}{\_ pixels}{\_ estimated}}}} & (30)\end{matrix}$

Referring back to FIG. 1, in some demonstrative embodiments, application160 may be configured to perform one or more operations to estimate thecamera distance, the lens distance and/or the one or more opticalparameters of the lens, for example, according to the sixth measurementscheme, e.g., as described below.

Reference is made to FIG. 22, which schematically illustrates ameasurement scheme 91500, in accordance with some demonstrativeembodiments. For example, one or more operations using of themeasurement scheme 91500 may be performed by a system, e.g., system 100(FIG. 1); a mobile device, e.g., device 102 (FIG. 1); a server, e.g.,server 170 (FIG. 1); a display, e.g., display 130 (FIG. 1); and/or anapplication, e.g., application 160 (FIG. 1).

In some demonstrative embodiments, measurement scheme 91500 may beconfigured to determine one or more optical parameters of a lens 91510,for example, according to the sixth measurement scheme.

In some demonstrative embodiments, as shown in measurement scheme 91500,the lens 91510 may be placed at a distance, denoted L1, e.g., the lensdistance, between lens 91510 and a display 91530. For example, display91530 may perform the functionality of display 130 (FIG. 1).

In some demonstrative embodiments, the distance L1, of the frame fromthe display 91530 may be known.

In some demonstrative embodiments, the lens distance L1 may be known,for example, due to placing the frame at a predefined distance, placingthe temple arms extended against the display, measuring the distance ofthe frame from the display and/or using any other method to determinethe distance of the frame from the display or from the camera.

In some demonstrative embodiments, device 91502, may be located at anygiven distance, denoted L2, e.g., a predefined distance or an arbitrarydistance, from the display 91530, e.g., the camera distance, forexample, as long as device 91502 is able to capture an image of theobject displayed on the display 91530, e.g., through the lens 91510.

In some demonstrative embodiments, the camera distance L2, between thedisplay and the device, may be calculated from an object having a knownsize that that may be displayed on display 91530, for example, and oneor more parameters of the camera 91502, e.g., a focal length, a field ofview, and/or a sensor pitch, e.g., as described below.

Referring back to FIG. 1, in some demonstrative embodiments, device 102may perform one or more operations, for example, to calibrate one ormore elements of the frame, e.g., as described below.

In some demonstrative embodiments, the frame may be calibrated, forexample, by placing the frame against the display 130 and capturing animage including the frame and the display 130, which may present acalibration object having known sizes.

In some demonstrative embodiments, an auto-detection or a manualdetection of a feature of the frame may be scaled, for example, usingthe calibration object displayed upon the display 130.

In some demonstrative embodiments, the frame may be calibrated, forexample, by placing the frame at a known distance from the display 130,e.g., as described below.

In some demonstrative embodiments, by extending the temple arms of theeyeglasses and placing them against the display 130, the distance of theframe surrounding the lenses from the display 130 may be regarded asabout 145 mm.

In some demonstrative embodiments, a feature of the frame may becalibrated, for example, according to the magnification of the displayedimage of the calibration object, e.g., for the distance of 145 mm, andone or more camera lens properties.

In some demonstrative embodiments, the frame can be calibrated, forexample, using the fact that the maximum magnification occurs, forexample, when the eyeglasses are just in the middle between the display130 and camera 118.

In some demonstrative embodiments, using this fact it may be determinedthat the distance of an actual location of the frame is half a measureddistance between the device 102 and the display 130.

In some demonstrative embodiments, using a known distance converted intoan absolute magnification, where the focal length and sensor pixel pitchare given may be determined, e.g., as follows:

$\begin{matrix}{h = \frac{h_{pixels}^{\prime}*{pitch}*\left( {L - f} \right)}{2f}} & (31)\end{matrix}$wherein h′_(pixels) is the amount of pixels that the frame feature isaccommodating on the sensor, pitch is the distance from one pixel to anadjacent pixel, L is the distance between the display and the deviceand/or f is the focal length of the camera.

In some demonstrative embodiments, device 102 may perform one or moreoperations, for example, to calibrate a display size, for example, ofdisplay 130, e.g., as described below.

In some demonstrative embodiments, calibration of the display 130 may beperformed, for example, by capturing an image of an object with a knownsize, placed against the display.

In some demonstrative embodiments, the object with known size may be astandard magnetic card, a CD media, a ruler, a battery (AA, AAA . . . )and/or the like.

In some demonstrative embodiments, the object with known size may be theeyeglasses temple arm length. The arm length is typically 13.5 cm to 15cm. This accuracy may be enough for further estimations.

In some demonstrative embodiments, the temple arm length may be scribedon an arm of the eyeglasses and the length may be used for the displaycalibration.

In some demonstrative embodiments, calibrating the display may includecomparing an object with known dimensions to a displayed feature havinga known amount of pixels.

In some demonstrative embodiments, a scaling factor, denoted scaling,may be determined, e.g., as follows:

$\begin{matrix}{{scaling} = {\frac{s_{{captured}.{pixels}}}{{ref}_{{captured}.{pixels}}}*{\frac{L_{{absolute}.\dim}}{S_{{displayed}.{pixels}}}\left\lbrack {{mm}\text{/}{pixel}} \right\rbrack}}} & (32)\end{matrix}$

In some demonstrative embodiments, a scaling of the display may beapplied to display a feature having absolute size on the display.

In some demonstrative embodiments, calibration of the display may beperformed, for example, by capturing an image of the display 130 at aknown distance, while considering the effective focal length of thecamera lens, and/or the field of view of the lens of the camera or thesensor pitch.

In some demonstrative embodiments, the magnification, denoted M, of animage having a size h of an object of size H, positioned at a cameradistance L from the camera having a focal length f, may be determined,e.g., as follows:

$\begin{matrix}{{M \equiv \frac{h}{H}} = \frac{f}{L}} & (33)\end{matrix}$

In some demonstrative embodiments, am actual size h of the image on thedevice may be calculated, for example, based on a sensor pitchp[μm/pixel] e.g., as follows:h=h _(pix) ·p  (34)wherein h_(pix) is the number of pixels the image span on the device.

In some demonstrative embodiments, the absolute size H of the image onthe display may be determined, e.g., as follows:

$\begin{matrix}{H = \frac{{p \cdot h_{pix}}L}{f}} & (35)\end{matrix}$

In some demonstrative embodiments, once the displayed object withdimension of H has been determined, a scaling to the display can beapplied to display a known absolute size of features on the display.

In another embodiment, the scaling factor may be considered whenevaluating images from the display, without scaling the image beingdisplayed on the display.

For example, a screen having a width of 375 mm may accommodate 1024pixels for this dimension. A calibration object of 100 pixels may bedisplayed on the display and may be captured with a camera. A known sizeobject (“a reference object”) having a dimension of 300 mm may be placedon the display.

In some demonstrative embodiments, an image analysis of an imageincluding the image of the calibration object and the image of thereference object, may show that the reference object accommodates 120pixels and the calibration object accommodates 60 pixels. Accordingly,the scaling factor may be 1.5 mm/pixel.

In some demonstrative embodiments, the image presented on the displaymay be scaled, for example, to match the predetermined known sizeobject.

In one example, in order to display an image having a dimension of 60mm, an image having 40 pixels should be displayed.

In another example, the same amount of pixels on every screen may bedisplayed, and the scaling factor may be considered, for example, whencapturing an image. According to this example, the scaling factor may beconsidered to evaluate the absolute dimension of an object, e.g., thathas been displayed on the display.

Reference is made to FIG. 23, which schematically illustrates acalibration scheme 91600, in accordance with some demonstrativeembodiments. For example, calibration scheme 91600 may be implemented tocalibrate display 130 (FIG. 1).

In some demonstrative embodiments, as shown in FIG. 23, a referenceobject 91604, e.g. a credit card, may be placed against a display 91630.

In other embodiments, the reference object 91604 may include extendedeyeglasses temple arms placed against the display.

In some demonstrative embodiments, an image capturing device 91602,e.g., camera 118 (FIG. 1), may capture an image of the reference object91604.

In some demonstrative embodiments, as shown in FIG. 23, the display91630 may be triggered, e.g., by application 160 (FIG. 1), display oneor more calibration objects 91606, e.g., an ellipsoid or borderlineshapes.

In some demonstrative embodiments, a pixel to millimeter ratio ofdisplay 91630 may be determined, for example, by comparing the referenceobject 91604 to the calibration objects 91606, e.g., as described above.

In some demonstrative embodiments, the calibration objects 91606 may beconstituted from different channels of colors, e.g., Red-Green-Blue, sothat the auto identification of the feature and the object can beutilized.

Referring back to FIG. 1, In some demonstrative embodiments, application160 may be configured to analyze one or more parameters, visual effects,optical effects and/or attributes with respect to the image of acalibration object, e.g., displayed on display 130.

In some demonstrative embodiments, the calibration object may include ashape and/or color.

In some demonstrative embodiments, device 102 may perform an analysisfor a magnification of the shape for a certain angle corresponding to afocal power at the same angle.

In some demonstrative embodiments, a spherical lens may create, forexample, a uniform magnification at all angles.

In some demonstrative embodiments, a cylindrical lens may cause, forexample, maximum magnification at an angle corresponding to the angle ofthe cylindrical lens, and no relative magnification at the angleperpendicular to the cylindrical angle.

In some demonstrative embodiments, a combination of a spherical lens anda cylindrical lens may create, for example, two perpendicular angles inwhich different relative magnification are apparent.

In some demonstrative embodiments, angles corresponding to the angle ofthe cylinder, and the magnification on each angle may be the basis forfocal length calculation.

In some demonstrative embodiments, a result of two focal powers may beshown, for example, due to the cylindrical lens.

In some demonstrative embodiments, the difference between the two focalpowers may be considered as the cylindrical power.

Reference is made to FIG. 24, which schematically illustrates an image91700 of an object 91702 captured via a lens 91710, in accordance withsome demonstrative embodiments.

For example, application 160 (FIG. 1) may be configured to determine oneor more parameters of lens 91710 based on the image of object 91102.

In some demonstrative embodiments, as shown in FIG. 24, image 91700 mayillustrate the effect of magnification of two focal powers of lens91710.

In some demonstrative embodiments, as shown in FIG. 24, object 91702 maybe composed of radial lines in several radii.

In some demonstrative embodiments, as shown in FIG. 24, the two focalpowers of a lens 91710 may create two magnifications.

In some demonstrative embodiments, as shown in FIG. 24, since bothpowers are negative, the two focal powers of a lens 91710 may create twominifications.

In some demonstrative embodiments, as shown in FIG. 24, measuring thelength of each radial line in every angle, may demonstrate that thelength varies, which is the effect of the magnification of two focalpowers that are perpendicular to one another.

In some demonstrative embodiments, as shown in FIG. 24, this effect maycreate lines in the image that show a maximal magnification at an angle91712, and a minimal magnification at a perpendicular angle 91714.

In some demonstrative embodiments, these two magnifications may be used,e.g., by application 160 (FIG. 1), to determine the two focal powers,and the angle at which the largest magnification occurs may be used, forexample, by application 160 (FIG. 1), to determine the angle of thecylinder.

In some demonstrative embodiments, as shown in FIG. 24, a circularsymmetric object can be utilized as object 91702. In this case the imagemay go through a magnification change, which for cylindrical lens, willresult in an elliptical shape.

In some demonstrative embodiments, lens power, lens cylinder powerand/or cylinder angle can be extracted, e.g., by application 160 (FIG.1), for example, by studying total magnification, and the ratio betweenthe long and short ellipse axes and the ellipse angle.

Reference is made to FIG. 25, which schematically illustrates an image91800 of an object 91802, in accordance with some demonstrativeembodiments.

In some demonstrative embodiments, as shown in FIG. 25, object 91802 maybe partially captured via a lens 91810, e.g., while other portions ofobject 91802 may be captured not thorough lens 91810.

For example, application 160 (FIG. 1) may be configured to determine oneor more parameters of lens 91810 based on the image of object 91802.

In some demonstrative embodiments, as shown in FIG. 25, object 91802 mayinclude an object, which may be composed of radial lines in severalradii, each line may be composed of a dashed line and different radiimay be designated by different colors or different line types.

In some demonstrative embodiments, the use of object 91802, e.g.,including the dashed line, may assist to determine the magnification,for example, since the spatial frequency of each line changes underdifferent magnification.

Reference is made to FIG. 26, which schematically illustrates an image91900 of an object 91902 captured via a lens 91910, in accordance withsome demonstrative embodiments. For example, application 160 (FIG. 1)may be configured to determine one or more parameters of lens 91910based on the image of object 91902.

In some demonstrative embodiments, as shown in FIG. 26, lens 91910 mayinclude a spherical and cylindrical lens.

In some demonstrative embodiments, as shown in FIG. 26, the capturedimage 91900 of object 91902 may illustrate a change of magnificationthat creates a maximum magnification at an angle 91912, and a minimummagnification at a perpendicular angle 91914.

In some demonstrative embodiments, as shown in FIG. 26, the capturedimage 91900 may illustrate a spatial frequency in lines at differentmeridians, which may be caused by a different magnification permeridian.

In some demonstrative embodiments, it may be apparent that thecylindrical effect causes the equal radial lines to create an ellipticalshape.

Reference is made to FIG. 27, which schematically illustrates an image92000 of an object 92002 captured via a lens 92010, in accordance withsome demonstrative embodiments.

For example, application 160 (FIG. 1) may be configured to determine oneor more parameters of lens 92010 based on the image of object 92002.

In some demonstrative embodiments, as shown in FIG. 27, object 92002 mayinclude outlining of a line connecting all lines with the same radii.

In some demonstrative embodiments, as shown in FIG. 27, image 92000 mayshow how different perpendicular focal powers of lens 92010 may createtwo perpendicular magnifications that transform a circular shape into anelliptical shape.

In some demonstrative embodiments, as shown in FIG. 27, the largestmagnification may occur at an angle 92012, e.g., the cylindrical axis,and the minimum magnification may occur at a perpendicular angle 92014.

In some demonstrative embodiments, as shown in FIG. 27, the orientationof lens 92010 may be taken under consideration to calculate the absoluteaxis of the cylinder. For each of the ellipse axes the relativemagnification may be determined, and then the power of the lens may bedetermined.

In some demonstrative embodiments, due to different magnifications, forexample, due to a power of lens 92010, the object 92002 may be displayedat different scales on image 92000.

In some demonstrative embodiments, displaying several concentriccircular rings each with a different radius may enable to analyze bothpositive and negative magnification at different powers.

In some demonstrative embodiments, the magnification and cylinder inthese concentric rings may be further analyzed, using, for example, aFourier transform, e.g., by tracking the dominant frequency alongdifferent directions.

In some demonstrative embodiments, using several objects may provide theadvantage of improving accuracy, e.g., by averaging.

In other embodiments, object 92002 may include a dense grid line.

In some demonstrative embodiments, lens power, cylinder and aberrationscan be deduced, for example, by following the distortion within thedense grid line.

In some demonstrative embodiments, object 92002 may include chromoeffects, for example, to enable identifying certain features in image92000. For example, a minor defocus of colors, e.g., such as green andred, may result in a yellow color, e.g., where the two colors areadjacent.

Referring back to FIG. 1, in some demonstrative embodiments, application160 may be configured to determine that an image captured via the lensis captured through the center of the lens.

In some demonstrative embodiments, application 160 may be configured toperform one or more operations, methods and/or procedure to ensure thata minimum displacement from the center of the lens an image captured viathe lens.

Reference is made to FIG. 28, which schematically illustrates an ellipsecurve fit 92100 of a circular ring object 92102, in accordance with somedemonstrative embodiments.

In some demonstrative embodiments, ellipse curve fit 92100 may resultfrom capturing circular ring object 92102, for example, via acylindrical lens.

In some demonstrative embodiments, as shown in FIG. 28, an ellipse curvefit 92102 of a circular ring object image 92100 may be captured througha cylindrical test lens.

Referring back to FIG. 1, in some demonstrative embodiments, application160 may be configured to determine the one or more optical parameters ofa lens, for example, even without using display 130. For example,application 160 may be configured to determine a cylindrical power,and/or a cylinder angle and/or a spherical power of the lens, forexample, even without using display 130, e.g., as described below.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of a lens, for example,even without displaying an image on display 130.

In some demonstrative embodiments, application 160 may be configured todetermine the one or more optical parameters of a lens, for example,based on a captured image of an object having a known size, e.g., asdescribed below.

In some demonstrative embodiments, the one or more optical parameters ofthe lens such as sphere power, cylinder power and/or cylinder angle maybe found, for example, by using a camera or a Smartphone device and anobject of a known size.

In some demonstrative embodiments, by capturing an image of the objectof known size through the lens, the one or more optical parameters ofthe lens may be found.

In some demonstrative embodiments, the object of known size may include,for example, a coin having a known size, an Iris of the eye or acalibrated iris diameter of the eye, and/or any other object or element.

In some demonstrative embodiments, using the calibration object mayallow determining the one or more optical parameters of a lens, forexample, even without using a screen to display an object, and/or evenwithout calibration prior to measurement of the one or more opticalparameters of the lens.

In some demonstrative embodiments, the lens power and/or cylinderparameters may be deduced from a deformation of the observed image ofthe calibration object through the tested lens relative to an image ofthe calibration object, which may be observed directly without the testlens.

In some demonstrative embodiments, spectacle eyeglasses parameters,e.g., a sphere power, a cylinder power and/or a cylinder angle, may bedetermined, for example, using a camera or a Smartphone device, e.g.,even without using an external object of known size.

In some demonstrative embodiments, by capturing an image of an eye of awearer of the eyeglasses, it may be possible to analyze a change in anIris size of the Iris of the wearer resulting from the spectacleeyeglasses. For example, an image of the Iris with and without theeyeglasses may be compared and analyzed, e.g., to determine thespectacle eyeglasses parameters.

In some demonstrative embodiments, if needed, a cornea absolute size maybe calibrated, for example, using a known size object, e.g., a coin or acredit card.

Referring back to FIG. 1, in some demonstrative embodiments, application160 may be configured to determine a pupillary distance (PD) between afirst lens of eyeglasses and a second lens of the eyeglasses, e.g., asdescribed below.

In some demonstrative embodiments, application 160 may be configured toprocess an image of an object including a first element and a secondelement, e.g., as described below. In one example, application 160 maybe configured to cause display 130 to display the object.

In some demonstrative embodiments, the image may include a first imagedelement of the first element captured via the first lens and a secondimaged element of the second element captured via the second lens.

In some demonstrative embodiments, application 160 may be configured todetermine the pupillary distance between the first and second lenses,for example, based on at least a first distance between the first andsecond elements, and a second distance between the first and secondimaged elements, e.g., as described below.

Reference is made to FIG. 29, which schematically illustrates an image92200 of an object 92202, in accordance with some demonstrativeembodiments. For example, application 160 (FIG. 1) may cause display 130(FIG. 1) to display object 92202, and/or control camera 118 (FIG. 1) tocapture image 92200.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to determine a pupillary distance between a first lens 92210of eyeglasses and a second lens 92220 of the eyeglasses, for example,based on image 92200, e.g., as described below.

In some demonstrative embodiments, as shown in FIG. 29, object 92202 maybe displayed on a display device and may include a first circularlysymmetric object 92211 and a second circularly symmetric object 92221.In other embodiments, object 92202 may include any other additional oralternative shapes, objects and/or elements.

In some demonstrative embodiments, objects 92211 and 92221 may include aplurality of concentric circular rings. For example, each ring may havea different radius. In other embodiments, objects 92211 and 92221 mayinclude any other additional or alternative shape, object and/orelement.

In some demonstrative embodiments, as shown in FIG. 29, object 92202 mayinclude a first line element 92212 and a second line element 92222.

In some demonstrative embodiments, as shown in FIG. 29, line elements92212 and/or 92222 may include vertical line shape elements. In otherembodiments, line elements 92212 and/or 92222 may include any otheradditional or alternative shape, object and/or element.

In some demonstrative embodiments, as shown in FIG. 29, line element92212 may cross a center of circularly symmetric object 92211, and/orline element 92222 may cross a center of circularly symmetric object92221.

In some demonstrative embodiments, a distance 92203 between lineelements 92212 and 92222 may be preconfigured or preset. In one example,the distance 92203 may be configured based on a typical PD value or arange of PD values.

In some demonstrative embodiments, as shown in FIG. 29, image 92200 mayinclude a first imaged element 92214 of the first element 92212 capturedvia the first lens 92210.

In some demonstrative embodiments, as shown in FIG. 29, image 92200 mayinclude a second imaged element 92224 of the second element 92222captured via the second lens 92220.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to determine the pupillary distance of the lenses 92210 and92220 assembled in the eyeglasses, for example, based on at least afirst distance 92203 between elements 92212 and 92222, and a seconddistance 92213 between imaged elements 92214 and 92224, e.g., asdescribed below.

In some demonstrative embodiments, as shown in FIG. 29, line elements92212 and/or 92222 may assist in recognizing and/or evaluating a changeor difference between the distance 92213, e.g., as imaged through lenses92210 and 92220, and the distance 92203, e.g., imaged not through lenses92210 and 92220.

In some demonstrative embodiments, application 160 (FIG. 1) may utilizea distance of the eyeglasses from a camera, e.g., camera 118 (FIG. 1),which captures image 92202, and powers of the lenses 92210 and 92220,for example, to evaluate the PD from image 92202.

In some demonstrative embodiments, the distance 92203 may be known orcalibrated, e.g., as described above.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to determine the PD of the eyeglasses including lenses 220and 92220, for example, based on a first distance of the camera, e.g.,camera 118 (FIG. 1) from the display, e.g., display 130 (FIG. 1) (“thecamera-display distance”), and a second distance of lenses 92210 and92220 from the camera (“the camera-glasses distance”), e.g., asdescribed below.

In some demonstrative embodiments, the PD may be determined, forexample, based on the camera-display distance and the camera-glassesdistance, the powers of lenses 92210 and/or 92220, and/or distances92203 and 92213.

In some demonstrative embodiments, as shown in FIG. 29, image 2202 mayinclude one or more calibration elements 92206.

In some demonstrative embodiments, calibration elements 92206 may becaptured in image 92200 not via lenses 92210 and/or 92220.

In some demonstrative embodiments, one or more features of calibrationelements 92206 may be known, and/or measured. For example, distancesbetween calibration elements 92206 may be known and/or measured,diameters of calibration elements 92206 may be known and/or measured,and/or the like.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured, for example, to determine the camera-display distance, e.g.,based on image 92200.

In some demonstrative embodiments, circularly symmetric objects 92211and 92221 may be imaged simultaneously via the lenses 92210 and 92220,respectively, while the eyeglasses are located at the camera-glassesdistance, e.g., when image 92200 is captured.

In some demonstrative embodiments, a relative magnification ofcircularly symmetric objects 92211 and 92221 in image 92202, e.g., withrespect to the actual sizes of circularly symmetric objects 92211 and92221, may be calculated, for example, to determine the spherical powerand/or cylindrical power and/or axis of lenses 92210 and/or 92220, e.g.,separately.

In some demonstrative embodiments, a lateral displacement of the centersof circularly symmetric objects 92211 and 92221 may be seen, forexample, by displacement between line elements 92212 and/or 92222 andimaged line elements 92214 and 92224.

In some demonstrative embodiments, the lateral displacement may bederived from image 92200, for example, even without line elements 92212and/or 92222, for example, based on the centers of circularly symmetricobject 92211 and 92221, e.g., as the locations of the centers may bepredefined, e.g., with respect to calibration objects 92206.

In some demonstrative embodiments, a lateral displacement of an image ofan object through a lens may be determined, for example, based on one ormore parameters, e.g., including a lens lateral displacement from anoptical axis of the lens, a distance of the lens from the object, adistance of the camera from the object, and/or a power of the lens.

In some demonstrative embodiments, application 160 (FIG. 1) may beconfigured to determine the distance between the centers of the lenses92210 and 92220, the power of the lenses 92210 and/or 92220, and/or thecylinder power and axis of the lens, e.g., simultaneously, for example,based on the one or more parameters.

In some demonstrative embodiments, the distance of the eyeglasses fromthe camera, e.g., the camera-glasses distance, may be determined, forexample, based on a given PD of the eyeglasses, for example, using image92200, e.g., as described below with reference to FIG. 31.

Reference is made to FIG. 30, which schematically illustrates a methodof determining a pupillary distance of lenses of eyeglasses, inaccordance with some demonstrative embodiments. For example, one oroperations of the method of FIG. 30 may be performed by a system, e.g.,system 100 (FIG. 1); a mobile device, e.g., device 102 (FIG. 1); aserver, e.g., server 170 (FIG. 1); a display, e.g., display 130 (FIG.1); and/or an application, e.g., application 160 (FIG. 1).

As indicated at block 92302, the method may include displaying an objecthaving one or more known or calibrated sizes on a display. For example,application 160 (FIG. 1) may cause display 130 (FIG. 1) to displayobject 92202 (FIG. 29), e.g., as described above.

As indicated at block 92304, the method may include capturing an imageof the object through both lenses of the eyeglasses with a camera, whilethe camera is placed at a first distance from the object and at a seconddistance from the lenses. For example, application 160 (FIG. 1) maycause camera 118 (FIG. 1) to capture the image 92200 (FIG. 29) of object92202 (FIG. 29) via lenses 92210 and 92220 (FIG. 29), for example, whilethe camera 118 (FIG. 1) is at the camera-display distance and the lensis at the camera-glasses distance, e.g., as described above.

As indicated at block 92306, the method may include determining thedistance between imaged centers of the object imaged through each lens,and the distance between the centers of the object imaged without thelenses. For example, application 160 (FIG. 1) may be configured todetermine the distance 92213 (FIG. 29) and the distance 92203 (FIG. 29),e.g., as described above.

As indicated at block 92308, the method may include receiving and/ordetermining one or more parameters to enable a PD calculation, e.g., thefirst distance, the second distance, and/or the power of each lens. Forexample, application 160 (FIG. 1) may receive and/or determine thecamera-display distance, the camera-glasses distance, and/or the powersof lenses 92210 and 92220 (FIG. 29), e.g., as described above.

As indicated at block 92310, the method may include determining thedistance between centers of the lenses, based on the one or moreparameters. For example, application 160 (FIG. 1) may determine the PDof the eyeglasses, for example, based on the camera-glasses distance,the camera-display distance, and/or the powers of lenses 92210 and 92220(FIG. 29), e.g., as described above.

Referring back to FIG. 1, in some demonstrative embodiments, application160 may be configured to determine a distance between camera 118 and theeyeglasses (“the camera-lens distance”), for example, based on apupillary distance between lenses of the eyeglasses, e.g., as describedbelow.

Reference is made to FIG. 31, which schematically illustrates a methodof determining a distance between a camera and eyeglasses, in accordancewith some demonstrative embodiments. For example, one or operations ofthe method of FIG. 31 may be performed by a system, e.g., system 100(FIG. 1); a mobile device, e.g., device 102 (FIG. 1); a server, e.g.,server 170 (FIG. 1); a display, e.g., display 130 (FIG. 1); and/or anapplication, e.g., application 160 (FIG. 1).

In some demonstrative embodiments, application 160 (FIG. 1) may performone or more operations of FIG. 31 to determine the camera-lensesdistance, for example, based on an estimated or preconfigured pupillarydistance of the lenses of the eyeglasses.

As indicated at block 92402, the method may include displaying an objecthaving one or more known or calibrated sizes on a display. For example,application 160 (FIG. 1) may cause display 130 (FIG. 1) to displayobject 92202 (FIG. 29), e.g., as described above.

As indicated at block 92404, the method may include capturing an imageof the object through both lenses of the eyeglasses with a camera, whilethe camera is placed at a first distance from the object and at a seconddistance from the lenses. For example, application 160 (FIG. 1) maycause camera 118 (FIG. 1) to capture the image 92200 (FIG. 29) of object92202 (FIG. 29) via lenses 92210 and 92220 (FIG. 29), for example, whilethe camera 118 (FIG. 1) is at the camera-display distance and the lensis at the camera-glasses distance, e.g., as described above.

As indicated at block 92406, the method may include determining thedistance between imaged centers of the object imaged through each lens,and the distance between the centers of the object imaged without thelenses. For example, application 160 (FIG. 1) may be configured todetermine the distance 92213 (FIG. 29) and the distance 92203 (FIG. 29),e.g., as described above.

As indicated at block 92408, the method may include receiving and/ordetermining one or more parameters, e.g., the PD of the eyeglasses, thefirst distance, and/or the power of each lens. For example, application160 (FIG. 1) may receive and/or determine the camera-display distance,the PD of the eyeglasses, and/or the powers of lenses 92210 and 92220(FIG. 29), e.g., as described above.

As indicated at block 92410, the method may include determining thecamera-lens distance, based on the one or more parameters. For example,application 160 (FIG. 1) may determine the camera-glasses distance, forexample, based on the camera-display distance, the PD of the eyeglasses,and/or the powers of lenses 92210 and 92220 (FIG. 29), e.g., asdescribed above.

Reference is made to FIG. 32, which schematically illustrates a methodof determining one or more optical parameters of a lens, in accordancewith some demonstrative embodiments. For example, one or operations ofthe method of FIG. 29 may be performed by a system, e.g., system 100(FIG. 1); a mobile device, e.g., device 102 (FIG. 1); a server, e.g.,server 170 (FIG. 1); a display, e.g., display 130 (FIG. 1); and/or anapplication, e.g., application 160 (FIG. 1).

As indicated at block 92502, the method may include processing at leastone image of an object captured via the lens. For example, application160 (FIG. 1) may process the at least one image captured via the lens ofthe object displayed over display 130 (FIG. 1), e.g., as describedabove.

As indicated at block 92504, the method may include determining the oneor more optical parameters of the lens based on the at least one image.For example, application 160 (FIG. 1) may determine the one or moreoptical parameters of the lens based on the at least one image, e.g., byperforming one or more operations as described above with respect to oneor more of FIGS. 1-21.

Reference is made to FIG. 33, which schematically illustrates a methodof determining one or more optical parameters of a lens of eyeglasses,in accordance with some demonstrative embodiments. For example, one oroperations of the method of FIG. 33 may be performed by a system, e.g.,system 100 (FIG. 1); a computing device, e.g., device 102 (FIG. 1); aserver, e.g., server 170 (FIG. 1); a display, e.g., display 130 (FIG.1); and/or an application, e.g., application 160 (FIG. 1).

As indicated at block 3302, the method may include processing at leastone captured image of at least one reflection of a flash on a lens ofeyeglasses. For example, application 160 (FIG. 1) may process the atleast one captured image of the at least one reflection of the flash 122(FIG. 1) on the lens of the eyeglasses, e.g., as described above.

As indicated at block 3304, the method may include determining one ormore optical parameters of the lens based at least on the at least onecaptured image. For example, application 160 (FIG. 1) may determine theone or more optical parameters of the lens based at least on the atleast one captured image, e.g., as described above.

Reference is made to FIG. 34, which schematically illustrates a methodof determining one or more optical parameters of a lens of eyeglasses,in accordance with some demonstrative embodiments. For example, one oroperations of the method of FIG. 34 may be performed by a system, e.g.,system 100 (FIG. 1); a computing device, e.g., device 102 (FIG. 1); aserver, e.g., server 170 (FIG. 1); a display, e.g., display 130 (FIG.1); and/or an application, e.g., application 160 (FIG. 1).

As indicated at block 3402, the method may include triggering capturingof at least one image by a camera of at least one reference object via alens of eyeglasses. For example, application 160 (FIG. 1) may triggerthe capturing of the at least one image by the camera 118 (FIG. 1) ofthe at least one reference object via the lens of the eyeglasses, e.g.,as described above.

As indicated at block 3404, the method may include determining arelative angle between a plane of the lens and a plane of the camera.For example, application 160 (FIG. 1) may determine the relative anglebetween the plane of the lens and the plane of the camera 118 (FIG. 1),e.g., as described above.

As indicated at block 3406, the method may include determining one ormore optical parameters of the lens based at least on the relative angleand the at least one image. For example, application 160 (FIG. 1) maydetermine the one or more optical parameters of the lens based at leaston the relative angle and the at least one captured image, e.g., asdescribed above.

Reference is made to FIG. 35, which schematically illustrates a productof manufacture 3500, in accordance with some demonstrative embodiments.Product 3500 may include one or more tangible computer-readablenon-transitory storage media 3502, which may include computer-executableinstructions, e.g., implemented by logic 3504, operable to, whenexecuted by at least one computer processor, enable the at least onecomputer processor to implement one or more operations at device 102(FIG. 1), server 170 (FIG. 1), display 130 (FIG. 1), and/or application160 (FIG. 1), and/or to perform, trigger and/or implement one or moreoperations, communications and/or functionalities according to one ormore FIGS. 1-34, and/or one or more operations described herein. Thephrase “non-transitory machine-readable medium” is directed to includeall computer-readable media, with the sole exception being a transitorypropagating signal.

In some demonstrative embodiments, product 3500 and/or machine-readablestorage medium 3502 may include one or more types of computer-readablestorage media capable of storing data, including volatile memory,non-volatile memory, removable or non-removable memory, erasable ornon-erasable memory, writeable or re-writeable memory, and the like. Forexample, machine-readable storage medium 3502 may include, RAM, DRAM,Double-Data-Rate DRAM (DDR-DRAM), SDRAM, static RAM (SRAM), ROM,programmable ROM (PROM), erasable programmable ROM (EPROM), electricallyerasable programmable ROM (EEPROM), Compact Disk ROM (CD-ROM), CompactDisk Recordable (CD-R), Compact Disk Rewriteable (CD-RW), flash memory(e.g., NOR or NAND flash memory), content addressable memory (CAM),polymer memory, phase-change memory, ferroelectric memory,silicon-oxide-nitride-oxide-silicon (SONOS) memory, a disk, a floppydisk, a hard drive, an optical disk, a magnetic disk, a card, a magneticcard, an optical card, a tape, a cassette, and the like. Thecomputer-readable storage media may include any suitable media involvedwith downloading or transferring a computer program from a remotecomputer to a requesting computer carried by data signals embodied in acarrier wave or other propagation medium through a communication link,e.g., a modem, radio or network connection.

In some demonstrative embodiments, logic 3504 may include instructions,data, and/or code, which, if executed by a machine, may cause themachine to perform a method, process and/or operations as describedherein. The machine may include, for example, any suitable processingplatform, computing platform, computing device, processing device,computing system, processing system, computer, processor, or the like,and may be implemented using any suitable combination of hardware,software, firmware, and the like.

In some demonstrative embodiments, logic 3504 may include, or may beimplemented as, software, a software module, an application, a program,a subroutine, instructions, an instruction set, computing code, words,values, symbols, and the like. The instructions may include any suitabletype of code, such as source code, compiled code, interpreted code,executable code, static code, dynamic code, and the like. Theinstructions may be implemented according to a predefined computerlanguage, manner or syntax, for instructing a processor to perform acertain function. The instructions may be implemented using any suitablehigh-level, low-level, object-oriented, visual, compiled and/orinterpreted programming language, such as C, C++, Java, BASIC, Matlab,Pascal, Visual BASIC, assembly language, machine code, and the like.

EXAMPLES

The following examples pertain to further embodiments.

Example 1 includes a product comprising one or more tangiblecomputer-readable non-transitory storage media comprisingcomputer-executable instructions operable to, when executed by at leastone computer processor, enable the at least one computer processor tocause a computing device to process at least one captured image of atleast one reflection of a flash on a lens of eyeglasses; and determineone or more optical parameters of the lens based at least on the atleast one captured image.

Example 2 includes the subject matter of Example 1, and optionally,wherein the captured image comprises an image captured by a camera, theinstructions, when executed, cause the computing device to determine theone or more optical parameters of the lens based on the at least onereflection and a relative angle between a plane of the lens and a planeof the camera.

Example 3 includes the subject matter of Example 2, and optionally,wherein the instructions, when executed, cause the computing device todetermine the relative angle based on the at least one reflection.

Example 4 includes the subject matter of Example 2 or 3, and optionally,wherein the at least one reflection comprises a first reflection of theflash on a front surface of the lens and a second reflection of theflash on a back surface of the lens, the instructions, when executed,cause the computing device to determine the relative angle based on atleast one displacement between the first and second reflections.

Example 5 includes the subject matter of Example 4, and optionally,wherein the at least one displacement comprises at least one of avertical displacement or a horizontal displacement.

Example 6 includes the subject matter of any one of Examples 2-5, andoptionally, wherein the instructions, when executed, cause the computingdevice to determine the relative angle based on a relative location ofthe at least one reflection relative to a center of the lens.

Example 7 includes the subject matter of Example 6, and optionally,wherein the captured image comprises a first reference object image of afirst reference object captured via the lens and a second referenceobject image of a second reference object captured not via the lens, theinstructions, when executed, cause the computing device to determine thecenter of the lens based on the first reference object image and thesecond reference object image.

Example 8 includes the subject matter of any one of Examples 1-7, andoptionally, wherein the instructions, when executed, cause the computingdevice to determine a spherical power of the lens based on a diametersize of the at least one reflection in the captured image.

Example 9 includes the subject matter of any one of Examples 1-8, andoptionally, wherein the instructions, when executed, cause the computingdevice to determine at least one of a cylindrical power of the lens or acylindrical axis of the lens based on a deformation of the at least onereflection in the captured image.

Example 10 includes the subject matter of any one of Examples 1-9, andoptionally, wherein the captured image comprises a reference objectimage of a reference object captured by a camera via the lens, theinstructions, when executed, cause the computing device to determine oneor more estimated optical parameters of the lens based on a comparisonbetween the reference object and the reference object image; todetermine a relative angle between a plane of the lens and a plane ofthe camera based on the at least one reflection; and to determine theone or more optical parameters of the lens based on the relative angleand the one or more estimated optical parameters.

Example 11 includes the subject matter of Example 10, and optionally,wherein the instructions, when executed, cause the computing device todetermine an estimated spherical power of the lens based on amagnification between a reference dimension of the reference object andan imaged dimension of the reference dimension in the reference objectimage, and to determine a spherical power of the lens based on therelative angle and the estimated spherical power.

Example 12 includes the subject matter of Example 10 or 11, andoptionally, wherein the instructions, when executed, cause the computingdevice to determine at least one of an estimated cylindrical power ofthe lens or an estimated cylindrical axis of the lens based on adeformation between one or more reference dimensions of the referenceobject and one or more respective imaged dimensions of the one or morereference dimensions in the reference object image, and to determine atleast one of a cylindrical power of the lens or a cylindrical axis ofthe lens based on the relative angle and at least one of the estimatedcylindrical power or the estimated cylindrical axis.

Example 13 includes the subject matter of any one of Examples 1-12, andoptionally, wherein the at least one reflection comprises a firstreflection of the flash from a front surface of the lens, and a secondreflection of the flash from a back surface of the lens.

Example 14 includes the subject matter of Example 13, and optionally,wherein the captured image comprises a reference object image of areference object captured via the lens, the instructions, when executed,cause the computing device to determine the one or more opticalparameters of the lens based on a comparison between the referenceobject and the reference object image when the first and secondreflections coincide in the captured image.

Example 15 includes the subject matter of Example 14, and optionally,wherein the instructions, when executed, cause the computing device totrigger an instruction to a user to rotate the eyeglasses at least untilthe first and second reflections coincide.

Example 16 includes the subject matter of any one of Examples 1-15, andoptionally, wherein the instructions, when executed, cause the computingdevice to trigger capturing of the at least one captured image.

Example 17 includes the subject matter of any one of Examples 1-16, andoptionally, wherein the one or more optical parameters comprise at leasta spherical power of the lens.

Example 18 includes the subject matter of any one of Examples 1-17, andoptionally, wherein the one or more optical parameters comprise at leastone of a cylindrical power or a cylindrical axis of the lens.

Example 19 includes a mobile device comprising a camera to capture atleast one image of at least one reflection of a flash on a lens ofeyeglasses; and a lensometer module to determine one or more opticalparameters of the lens based at least on the at least one capturedimage.

Example 20 includes the subject matter of Example 19, and optionally,wherein the captured image comprises an image captured by a camera, thelensometer module to determine the one or more optical parameters of thelens based on the at least one reflection and a relative angle between aplane of the lens and a plane of the camera.

Example 21 includes the subject matter of Example 20, and optionally,wherein the lensometer module is to determine the relative angle basedon the at least one reflection.

Example 22 includes the subject matter of Example 20 or 21, andoptionally, wherein the at least one reflection comprises a firstreflection of the flash on a front surface of the lens and a secondreflection of the flash on a back surface of the lens, the lensometermodule to determine the relative angle based on at least onedisplacement between the first and second reflections.

Example 23 includes the subject matter of Example 22, and optionally,wherein the at least one displacement comprises at least one of avertical displacement or a horizontal displacement.

Example 24 includes the subject matter of any one of Examples 20-23, andoptionally, wherein the lensometer module is to determine the relativeangle based on a relative location of the at least one reflectionrelative to a center of the lens.

Example 25 includes the subject matter of Example 24, and optionally,wherein the captured image comprises a first reference object image of afirst reference object captured via the lens and a second referenceobject image of a second reference object captured not via the lens, thelensometer module to determine the center of the lens based on the firstreference object image and the second reference object image.

Example 26 includes the subject matter of any one of Examples 19-25, andoptionally, wherein the lensometer module is to determine a sphericalpower of the lens based on a diameter size of the at least onereflection in the captured image.

Example 27 includes the subject matter of any one of Examples 19-26, andoptionally, wherein the lensometer module is to determine at least oneof a cylindrical power of the lens or a cylindrical axis of the lensbased on a deformation of the at least one reflection in the capturedimage.

Example 28 includes the subject matter of any one of Examples 19-27, andoptionally, wherein the captured image comprises a reference objectimage of a reference object captured by a camera via the lens, thelensometer module to determine one or more estimated optical parametersof the lens based on a comparison between the reference object and thereference object image; to determine a relative angle between a plane ofthe lens and a plane of the camera based on the at least one reflection;and to determine the one or more optical parameters of the lens based onthe relative angle and the one or more estimated optical parameters.

Example 29 includes the subject matter of Example 28, and optionally,wherein the lensometer module is to determine an estimated sphericalpower of the lens based on a magnification between a reference dimensionof the reference object and an imaged dimension of the referencedimension in the reference object image, and to determine a sphericalpower of the lens based on the relative angle and the estimatedspherical power.

Example 30 includes the subject matter of Example 28 or 29, andoptionally, wherein the lensometer module is to determine at least oneof an estimated cylindrical power of the lens or an estimatedcylindrical axis of the lens based on a deformation between one or morereference dimensions of the reference object and one or more respectiveimaged dimensions of the one or more reference dimensions in thereference object image, and to determine at least one of a cylindricalpower of the lens or a cylindrical axis of the lens based on therelative angle and at least one of the estimated cylindrical power orthe estimated cylindrical axis.

Example 31 includes the subject matter of any one of Examples 19-30, andoptionally, wherein the at least one reflection comprises a firstreflection of the flash from a front surface of the lens, and a secondreflection of the flash from a back surface of the lens.

Example 32 includes the subject matter of Example 31, and optionally,wherein the captured image comprises a reference object image of areference object captured via the lens, the lensometer module todetermine the one or more optical parameters of the lens based on acomparison between the reference object and the reference object imagewhen the first and second reflections coincide in the captured image.

Example 33 includes the subject matter of Example 32, and optionally,wherein the lensometer module is to trigger an instruction to a user torotate the eyeglasses at least until the first and second reflectionscoincide.

Example 34 includes the subject matter of any one of Examples 19-33, andoptionally, wherein the lensometer module is to trigger capturing of theat least one captured image.

Example 35 includes the subject matter of any one of Examples 19-34, andoptionally, wherein the one or more optical parameters comprise at leasta spherical power of the lens.

Example 36 includes the subject matter of any one of Examples 19-35, andoptionally, wherein the one or more optical parameters comprise at leastone of a cylindrical power or a cylindrical axis of the lens.

Example 37 includes a method of determining one or more opticalparameters of a lens of eyeglasses, the method comprising processing atleast one captured image of at least one reflection of a flash on thelens of the eyeglasses; and determining the one or more opticalparameters of the lens based at least on the at least one capturedimage.

Example 38 includes the subject matter of Example 37, and optionally,wherein the captured image comprises an image captured by a camera, themethod comprising determining the one or more optical parameters of thelens based on the at least one reflection and a relative angle between aplane of the lens and a plane of the camera.

Example 39 includes the subject matter of Example 38, and optionally,comprising determining the relative angle based on the at least onereflection.

Example 40 includes the subject matter of Example 38 or 39, andoptionally, wherein the at least one reflection comprises a firstreflection of the flash on a front surface of the lens and a secondreflection of the flash on a back surface of the lens, the methodcomprising determining the relative angle based on at least onedisplacement between the first and second reflections.

Example 41 includes the subject matter of Example 40, and optionally,wherein the at least one displacement comprises at least one of avertical displacement or a horizontal displacement.

Example 42 includes the subject matter of any one of Examples 38-41, andoptionally, comprising determining the relative angle based on arelative location of the at least one reflection relative to a center ofthe lens.

Example 43 includes the subject matter of Example 42, and optionally,wherein the captured image comprises a first reference object image of afirst reference object captured via the lens and a second referenceobject image of a second reference object captured not via the lens, themethod comprising determining the center of the lens based on the firstreference object image and the second reference object image.

Example 44 includes the subject matter of any one of Examples 37-43, andoptionally, comprising determining a spherical power of the lens basedon a diameter size of the at least one reflection in the captured image.

Example 45 includes the subject matter of any one of Examples 37-44, andoptionally, comprising determining at least one of a cylindrical powerof the lens or a cylindrical axis of the lens based on a deformation ofthe at least one reflection in the captured image.

Example 46 includes the subject matter of any one of Examples 37-45, andoptionally, wherein the captured image comprises a reference objectimage of a reference object captured by a camera via the lens, themethod comprising determining one or more estimated optical parametersof the lens based on a comparison between the reference object and thereference object image; determining a relative angle between a plane ofthe lens and a plane of the camera based on the at least one reflection;and determining the one or more optical parameters of the lens based onthe relative angle and the one or more estimated optical parameters.

Example 47 includes the subject matter of Example 46, and optionally,comprising determining an estimated spherical power of the lens based ona magnification between a reference dimension of the reference objectand an imaged dimension of the reference dimension in the referenceobject image, and determining a spherical power of the lens based on therelative angle and the estimated spherical power.

Example 48 includes the subject matter of Example 46 or 47, andoptionally, comprising determining at least one of an estimatedcylindrical power of the lens or an estimated cylindrical axis of thelens based on a deformation between one or more reference dimensions ofthe reference object and one or more respective imaged dimensions of theone or more reference dimensions in the reference object image, anddetermining at least one of a cylindrical power of the lens or acylindrical axis of the lens based on the relative angle and at leastone of the estimated cylindrical power or the estimated cylindricalaxis.

Example 49 includes the subject matter of any one of Examples 37-48, andoptionally, wherein the at least one reflection comprises a firstreflection of the flash from a front surface of the lens, and a secondreflection of the flash from a back surface of the lens.

Example 50 includes the subject matter of Example 49, and optionally,wherein the captured image comprises a reference object image of areference object captured via the lens, the method comprisingdetermining the one or more optical parameters of the lens based on acomparison between the reference object and the reference object imagewhen the first and second reflections coincide in the captured image.

Example 51 includes the subject matter of Example 50, and optionally,comprising triggering an instruction to a user to rotate the eyeglassesat least until the first and second reflections coincide.

Example 52 includes the subject matter of any one of Examples 37-51, andoptionally, comprising triggering capturing of the at least one capturedimage.

Example 53 includes the subject matter of any one of Examples 37-52, andoptionally, wherein the one or more optical parameters comprise at leasta spherical power of the lens.

Example 54 includes the subject matter of any one of Examples 37-53, andoptionally, wherein the one or more optical parameters comprise at leastone of a cylindrical power or a cylindrical axis of the lens.

Example 55 includes an apparatus to determine one or more opticalparameters of a lens of eyeglasses, the apparatus comprising means forprocessing at least one captured image of at least one reflection of aflash on the lens of the eyeglasses; and means for determining the oneor more optical parameters of the lens based at least on the at leastone captured image.

Example 56 includes the subject matter of Example 55, and optionally,wherein the captured image comprises an image captured by a camera, theapparatus comprising means for determining the one or more opticalparameters of the lens based on the at least one reflection and arelative angle between a plane of the lens and a plane of the camera.

Example 57 includes the subject matter of Example 56, and optionally,comprising means for determining the relative angle based on the atleast one reflection.

Example 58 includes the subject matter of Example 55 or 57, andoptionally, wherein the at least one reflection comprises a firstreflection of the flash on a front surface of the lens and a secondreflection of the flash on a back surface of the lens, the apparatuscomprising means for determining the relative angle based on at leastone displacement between the first and second reflections.

Example 59 includes the subject matter of Example 58, and optionally,wherein the at least one displacement comprises at least one of avertical displacement or a horizontal displacement.

Example 60 includes the subject matter of any one of Examples 56-59, andoptionally, comprising means for determining the relative angle based ona relative location of the at least one reflection relative to a centerof the lens.

Example 61 includes the subject matter of Example 60, and optionally,wherein the captured image comprises a first reference object image of afirst reference object captured via the lens and a second referenceobject image of a second reference object captured not via the lens, theapparatus comprising means for determining the center of the lens basedon the first reference object image and the second reference objectimage.

Example 62 includes the subject matter of any one of Examples 55-61, andoptionally, comprising means for determining a spherical power of thelens based on a diameter size of the at least one reflection in thecaptured image.

Example 63 includes the subject matter of any one of Examples 55-62, andoptionally, comprising means for determining at least one of acylindrical power of the lens or a cylindrical axis of the lens based ona deformation of the at least one reflection in the captured image.

Example 64 includes the subject matter of any one of Examples 55-63, andoptionally, wherein the captured image comprises a reference objectimage of a reference object captured by a camera via the lens, theapparatus comprising means for determining one or more estimated opticalparameters of the lens based on a comparison between the referenceobject and the reference object image; determining a relative anglebetween a plane of the lens and a plane of the camera based on the atleast one reflection; and determining the one or more optical parametersof the lens based on the relative angle and the one or more estimatedoptical parameters.

Example 65 includes the subject matter of Example 64, and optionally,comprising means for determining an estimated spherical power of thelens based on a magnification between a reference dimension of thereference object and an imaged dimension of the reference dimension inthe reference object image, and determining a spherical power of thelens based on the relative angle and the estimated spherical power.

Example 66 includes the subject matter of Example 64 or 65, andoptionally, comprising means for determining at least one of anestimated cylindrical power of the lens or an estimated cylindrical axisof the lens based on a deformation between one or more referencedimensions of the reference object and one or more respective imageddimensions of the one or more reference dimensions in the referenceobject image, and determining at least one of a cylindrical power of thelens or a cylindrical axis of the lens based on the relative angle andat least one of the estimated cylindrical power or the estimatedcylindrical axis.

Example 67 includes the subject matter of any one of Examples 55-66, andoptionally, wherein the at least one reflection comprises a firstreflection of the flash from a front surface of the lens, and a secondreflection of the flash from a back surface of the lens.

Example 68 includes the subject matter of Example 67, and optionally,wherein the captured image comprises a reference object image of areference object captured via the lens, the apparatus comprising meansfor determining the one or more optical parameters of the lens based ona comparison between the reference object and the reference object imagewhen the first and second reflections coincide in the captured image.

Example 69 includes the subject matter of Example 68, and optionally,comprising means for triggering an instruction to a user to rotate theeyeglasses at least until the first and second reflections coincide.

Example 70 includes the subject matter of any one of Examples 55-69, andoptionally, comprising means for triggering capturing of the at leastone captured image.

Example 71 includes the subject matter of any one of Examples 55-70, andoptionally, wherein the one or more optical parameters comprise at leasta spherical power of the lens.

Example 72 includes the subject matter of any one of Examples 55-71, andoptionally, wherein the one or more optical parameters comprise at leastone of a cylindrical power or a cylindrical axis of the lens

Example 73 includes a product comprising one or more tangiblecomputer-readable non-transitory storage media comprisingcomputer-executable instructions operable to, when executed by at leastone computer processor, enable the at least one computer processor tocause a computing device to trigger capturing of at least one image by acamera of at least one reference object via a lens of eyeglasses;determine a relative angle between a plane of the lens and a plane ofthe camera; and determine one or more optical parameters of the lensbased at least on the relative angle and the at least one image.

Example 74 includes the subject matter of Example 73, and optionally,wherein the instructions, when executed, cause the computing device todetermine the relative angle based on a comparison between the referenceobject and at least one object image of the reference object in the atleast one image.

Example 75 includes the subject matter of Example 74, and optionally,wherein the at least one image comprises at least one reflection of aflash on the lens, the instructions, when executed, cause the computingdevice to determine one or more estimated optical parameters of the lensbased on the at least one reflection, and to determine the one or moreoptical parameters of the lens based on the relative angle and the oneor more estimated optical parameters of the lens.

Example 76 includes the subject matter of Example 75, and optionally,wherein the instructions, when executed, cause the computing device todetermine an estimated spherical power of the lens based on a diametersize of the at least one reflection in the image.

Example 77 includes the subject matter of Example 75 or 76, andoptionally, wherein the instructions, when executed, cause the computingdevice to determine at least one of an estimated cylindrical power ofthe lens or an estimated cylindrical axis of the lens based on adeformation of the at least one reflection in the image.

Example 78 includes the subject matter of any one of Examples 73-77, andoptionally, wherein the at least one image comprises at least onereflection of a flash on the lens, the instructions, when executed,cause the computing device to determine the relative angle based on theat least one reflection.

Example 79 includes the subject matter of Example 78, and optionally,wherein the at least one reflection comprises a first reflection of theflash on a front surface of the lens and a second reflection of theflash on a back surface of the lens, the instructions, when executed,cause the computing device to determine the relative angle based on atleast one displacement between the first and second reflections.

Example 80 includes the subject matter of Example 79, and optionally,wherein the at least one displacement comprises at least one of avertical displacement or a horizontal displacement.

Example 81 includes the subject matter of any one of Examples 78-80, andoptionally, wherein the instructions, when executed, cause the computingdevice to determine the relative angle based on a relative location ofthe at least one reflection relative to a center of the lens.

Example 82 includes the subject matter of Example 81, and optionally,wherein the image comprises a first reference object image of a firstreference object captured via the lens and a second reference objectimage of a second reference object captured not via the lens, theinstructions, when executed, cause the computing device to determine thecenter of the lens based on the first reference object image and thesecond reference object image.

Example 83 includes the subject matter of any one of Examples 78-82, andoptionally, wherein the instructions, when executed, cause the computingdevice to determine one or more estimated optical parameters of the lensbased on a comparison between the reference object and at least oneobject image of the reference object in the at least one image, and todetermine the one or more optical parameters of the lens based on therelative angle and the one or more estimated optical parameters of thelens.

Example 84 includes the subject matter of Example 83, and optionally,wherein the instructions, when executed, cause the computing device todetermine an estimated spherical power of the lens based on amagnification between a reference dimension of the reference object andan imaged dimension of the reference dimension in the reference objectimage, and to determine a spherical power of the lens based on therelative angle and the estimated spherical power.

Example 85 includes the subject matter of Example 83 or 84, andoptionally, wherein the instructions, when executed, cause the computingdevice to determine at least one of an estimated cylindrical power ofthe lens or an estimated cylindrical axis of the lens based on adeformation between one or more reference dimensions of the referenceobject and one or more respective imaged dimensions of the one or morereference dimensions in the reference object image, and to determine atleast one of a cylindrical power of the lens or a cylindrical axis ofthe lens based on the relative angle and at least one of the estimatedcylindrical power or the estimated cylindrical axis.

Example 86 includes the subject matter of any one of Examples 73-85, andoptionally, wherein the one or more optical parameters comprise at leasta spherical power of the lens.

Example 87 includes the subject matter of any one of Examples 73-86, andoptionally, wherein the one or more optical parameters comprise at leastone of a cylindrical power or a cylindrical axis of the lens.

Example 88 includes a mobile device comprising a camera to capture atleast one image of at least one reference object via a lens ofeyeglasses; and a lensometer module to determine a relative anglebetween a plane of the lens and a plane of the camera, and to determineone or more optical parameters of the lens based at least on therelative angle and the at least one image.

Example 89 includes the subject matter of Example 88, and optionally,wherein the lensometer module is to determine the relative angle basedon a comparison between the reference object and at least one objectimage of the reference object in the at least one image.

Example 90 includes the subject matter of Example 89, and optionally,wherein the at least one image comprises at least one reflection of aflash on the lens, the lensometer module to determine one or moreestimated optical parameters of the lens based on the at least onereflection, and to determine the one or more optical parameters of thelens based on the relative angle and the one or more estimated opticalparameters of the lens.

Example 91 includes the subject matter of Example 90, and optionally,wherein the lensometer module is to determine an estimated sphericalpower of the lens based on a diameter size of the at least onereflection in the image.

Example 92 includes the subject matter of Example 90 or 91, andoptionally, wherein the lensometer module is to determine at least oneof an estimated cylindrical power of the lens or an estimatedcylindrical axis of the lens based on a deformation of the at least onereflection in the image.

Example 93 includes the subject matter of any one of Examples 88-92, andoptionally, wherein the at least one image comprises at least onereflection of a flash on the lens, the lensometer module to determinethe relative angle based on the at least one reflection.

Example 94 includes the subject matter of Example 93, and optionally,wherein the at least one reflection comprises a first reflection of theflash on a front surface of the lens and a second reflection of theflash on a back surface of the lens, the lensometer module to determinethe relative angle based on at least one displacement between the firstand second reflections.

Example 95 includes the subject matter of Example 94, and optionally,wherein the at least one displacement comprises at least one of avertical displacement or a horizontal displacement.

Example 96 includes the subject matter of any one of Examples 93-95, andoptionally, wherein the lensometer module is to determine the relativeangle based on a relative location of the at least one reflectionrelative to a center of the lens.

Example 97 includes the subject matter of Example 96, and optionally,wherein the image comprises a first reference object image of a firstreference object captured via the lens and a second reference objectimage of a second reference object captured not via the lens, thelensometer module to determine the center of the lens based on the firstreference object image and the second reference object image.

Example 98 includes the subject matter of any one of Examples 93-97, andoptionally, wherein the lensometer module is to determine one or moreestimated optical parameters of the lens based on a comparison betweenthe reference object and at least one object image of the referenceobject in the at least one image, and to determine the one or moreoptical parameters of the lens based on the relative angle and the oneor more estimated optical parameters of the lens.

Example 99 includes the subject matter of Example 98, and optionally,wherein the lensometer module is to determine an estimated sphericalpower of the lens based on a magnification between a reference dimensionof the reference object and an imaged dimension of the referencedimension in the reference object image, and to determine a sphericalpower of the lens based on the relative angle and the estimatedspherical power.

Example 100 includes the subject matter of Example 99 or 99, andoptionally, wherein the lensometer module is to determine at least oneof an estimated cylindrical power of the lens or an estimatedcylindrical axis of the lens based on a deformation between one or morereference dimensions of the reference object and one or more respectiveimaged dimensions of the one or more reference dimensions in thereference object image, and to determine at least one of a cylindricalpower of the lens or a cylindrical axis of the lens based on therelative angle and at least one of the estimated cylindrical power orthe estimated cylindrical axis.

Example 101 includes the subject matter of any one of Examples 88-100,and optionally, wherein the one or more optical parameters comprise atleast a spherical power of the lens.

Example 102 includes the subject matter of any one of Examples 88-101,and optionally, wherein the one or more optical parameters comprise atleast one of a cylindrical power or a cylindrical axis of the lens.

Example 103 includes a method of determining one or more opticalparameters of a lens of eyeglasses, the method comprising capturing atleast one image by a camera of at least one reference object via a lensof eyeglasses; determining a relative angle between a plane of the lensand a plane of the camera; and determining one or more opticalparameters of the lens based at least on the relative angle and the atleast one image.

Example 104 includes the subject matter of Example 103, and optionally,comprising determining the relative angle based on a comparison betweenthe reference object and at least one object image of the referenceobject in the at least one image.

Example 105 includes the subject matter of Example 104, and optionally,wherein the at least one image comprises at least one reflection of aflash on the lens, the method comprising determining one or moreestimated optical parameters of the lens based on the at least onereflection, and determining the one or more optical parameters of thelens based on the relative angle and the one or more estimated opticalparameters of the lens.

Example 106 includes the subject matter of Example 105, and optionally,comprising determining an estimated spherical power of the lens based ona diameter size of the at least one reflection in the image.

Example 107 includes the subject matter of Example 105 or 106, andoptionally, comprising determining at least one of an estimatedcylindrical power of the lens or an estimated cylindrical axis of thelens based on a deformation of the at least one reflection in the image.

Example 108 includes the subject matter of any one of Examples 103-107,and optionally, wherein the at least one image comprises at least onereflection of a flash on the lens, the method comprising determining therelative angle based on the at least one reflection.

Example 109 includes the subject matter of Example 108, and optionally,wherein the at least one reflection comprises a first reflection of theflash on a front surface of the lens and a second reflection of theflash on a back surface of the lens, the method comprising determiningthe relative angle based on at least one displacement between the firstand second reflections.

Example 110 includes the subject matter of Example 109, and optionally,wherein the at least one displacement comprises at least one of avertical displacement or a horizontal displacement.

Example 111 includes the subject matter of any one of Examples 108-110,and optionally, comprising determining the relative angle based on arelative location of the at least one reflection relative to a center ofthe lens.

Example 112 includes the subject matter of Example 111, and optionally,wherein the image comprises a first reference object image of a firstreference object captured via the lens and a second reference objectimage of a second reference object captured not via the lens, the methodcomprising determining the center of the lens based on the firstreference object image and the second reference object image.

Example 113 includes the subject matter of any one of Examples 108-112,and optionally, comprising determining one or more estimated opticalparameters of the lens based on a comparison between the referenceobject and at least one object image of the reference object in the atleast one image, and determining the one or more optical parameters ofthe lens based on the relative angle and the one or more estimatedoptical parameters of the lens.

Example 114 includes the subject matter of Example 113, and optionally,comprising determining an estimated spherical power of the lens based ona magnification between a reference dimension of the reference objectand an imaged dimension of the reference dimension in the referenceobject image, and determining a spherical power of the lens based on therelative angle and the estimated spherical power.

Example 115 includes the subject matter of Example 113 or 114, andoptionally, comprising determining at least one of an estimatedcylindrical power of the lens or an estimated cylindrical axis of thelens based on a deformation between one or more reference dimensions ofthe reference object and one or more respective imaged dimensions of theone or more reference dimensions in the reference object image, anddetermining at least one of a cylindrical power of the lens or acylindrical axis of the lens based on the relative angle and at leastone of the estimated cylindrical power or the estimated cylindricalaxis.

Example 116 includes the subject matter of any one of Examples 103-115,and optionally, wherein the one or more optical parameters comprise atleast a spherical power of the lens.

Example 117 includes the subject matter of any one of Examples 103-116,and optionally, wherein the one or more optical parameters comprise atleast one of a cylindrical power or a cylindrical axis of the lens.

Example 118 includes an apparatus to determine one or more opticalparameters of a lens of eyeglasses, the apparatus comprising means forcapturing at least one image by a camera of at least one referenceobject via a lens of eyeglasses; means for determining a relative anglebetween a plane of the lens and a plane of the camera; and means fordetermining one or more optical parameters of the lens based at least onthe relative angle and the at least one image.

Example 119 includes the subject matter of Example 118, and optionally,comprising means for determining the relative angle based on acomparison between the reference object and at least one object image ofthe reference object in the at least one image.

Example 120 includes the subject matter of Example 119, and optionally,wherein the at least one image comprises at least one reflection of aflash on the lens, the apparatus comprising means for determining one ormore estimated optical parameters of the lens based on the at least onereflection, and determining the one or more optical parameters of thelens based on the relative angle and the one or more estimated opticalparameters of the lens.

Example 121 includes the subject matter of Example 120, and optionally,comprising means for determining an estimated spherical power of thelens based on a diameter size of the at least one reflection in theimage.

Example 122 includes the subject matter of Example 120 or 121, andoptionally, comprising means for determining at least one of anestimated cylindrical power of the lens or an estimated cylindrical axisof the lens based on a deformation of the at least one reflection in theimage.

Example 123 includes the subject matter of any one of Examples 118-122,and optionally, wherein the at least one image comprises at least onereflection of a flash on the lens, the apparatus comprising means fordetermining the relative angle based on the at least one reflection.

Example 124 includes the subject matter of Example 123, and optionally,wherein the at least one reflection comprises a first reflection of theflash on a front surface of the lens and a second reflection of theflash on a back surface of the lens, the apparatus comprising means fordetermining the relative angle based on at least one displacementbetween the first and second reflections.

Example 125 includes the subject matter of Example 124, and optionally,wherein the at least one displacement comprises at least one of avertical displacement or a horizontal displacement.

Example 126 includes the subject matter of any one of Examples 123-125,and optionally, comprising means for determining the relative anglebased on a relative location of the at least one reflection relative toa center of the lens.

Example 127 includes the subject matter of Example 126, and optionally,wherein the image comprises a first reference object image of a firstreference object captured via the lens and a second reference objectimage of a second reference object captured not via the lens, theapparatus comprising means for determining the center of the lens basedon the first reference object image and the second reference objectimage.

Example 128 includes the subject matter of any one of Examples 123-127,and optionally, comprising means for determining one or more estimatedoptical parameters of the lens based on a comparison between thereference object and at least one object image of the reference objectin the at least one image, and determining the one or more opticalparameters of the lens based on the relative angle and the one or moreestimated optical parameters of the lens.

Example 129 includes the subject matter of Example 128, and optionally,comprising means for determining an estimated spherical power of thelens based on a magnification between a reference dimension of thereference object and an imaged dimension of the reference dimension inthe reference object image, and determining a spherical power of thelens based on the relative angle and the estimated spherical power.

Example 130 includes the subject matter of Example 128 or 129, andoptionally, comprising means for determining at least one of anestimated cylindrical power of the lens or an estimated cylindrical axisof the lens based on a deformation between one or more referencedimensions of the reference object and one or more respective imageddimensions of the one or more reference dimensions in the referenceobject image, and determining at least one of a cylindrical power of thelens or a cylindrical axis of the lens based on the relative angle andat least one of the estimated cylindrical power or the estimatedcylindrical axis.

Example 131 includes the subject matter of any one of Examples 118-130,and optionally, wherein the one or more optical parameters comprise atleast a spherical power of the lens.

Example 132 includes the subject matter of any one of Examples 118-131,and optionally, wherein the one or more optical parameters comprise atleast one of a cylindrical power or a cylindrical axis of the lens.

Functions, operations, components and/or features described herein withreference to one or more embodiments, may be combined with, or may beutilized in combination with, one or more other functions, operations,components and/or features described herein with reference to one ormore other embodiments, or vice versa.

While certain features have been illustrated and described herein, manymodifications, substitutions, changes, and equivalents may occur tothose skilled in the art. It is, therefore, to be understood that theappended claims are intended to cover all such modifications and changesas fall within the true spirit of the disclosure.

What is claimed is:
 1. A product comprising one or more tangiblecomputer-readable non-transitory storage media comprisingcomputer-executable instructions operable to, when executed by at leastone computer processor, enable the at least one computer processor tocause a computing device to: identify an imaged object in an imagecaptured by an image capturing device, the imaged object comprising animage of an object as captured by the image capturing device via a lens;determine an angle-based value, the angle-based value is based on arelative angle between a plane of the lens and a plane of the imagecapturing device when the image is captured; and determine one or moreparameters of the lens based on the angle-based value and the imagedobject.
 2. The product of claim 1, wherein the instructions, whenexecuted, cause the computing device to determine the angle-based valuebased on one or more elements in the image captured by the imagecapturing device.
 3. The product of claim 2, wherein the instructions,when executed, cause the computing device to identify an imagedreference element in the image captured by the image capturing device,and to determine the angle-based value based on a dimension of theimaged reference element.
 4. The product of claim 1, wherein theinstructions, when executed, cause the computing device to determine theangle-based value based on an image of eyeglasses comprising the lens.5. The product of claim 1, wherein the instructions, when executed,cause the computing device to determine the one or more parameters ofthe lens based on a plurality of images captured by the image capturingdevice, the plurality of images corresponding to a plurality of relativeangles between the plane of the lens and the plane of the imagecapturing device, wherein a first image in the plurality of imagescomprises a first image of the object as captured by the image capturingdevice via the lens at a first relative angle, and wherein a secondimage in the plurality of images comprises a second image of the objectas captured by the image capturing device via the lens at a secondrelative angle different from the first relative angle.
 6. The productof claim 5, wherein the instructions, when executed, cause the computingdevice to determine the one or more parameters of the lens based on aplurality of estimated parameter values corresponding to the pluralityof relative angles, the plurality of estimated parameter valuescomprising a first estimated value of a parameter of the lens based onthe first image, and a second estimated value of the parameter of thelens based on the second image.
 7. The product of claim 6, wherein theinstructions, when executed, cause the computing device to determine theone or more parameters of the lens by minimizing a predefined functionover the plurality of relative angles, wherein the predefined functionis based on a difference between a calculated value of the parameter ofthe lens for a particular relative angle and an estimated value of theparameter of the lens for the particular relative angle, wherein thecalculated value of the parameter of the lens for the particularrelative angle is based on a nominal value of the parameter of the lensand on the particular relative angle, and wherein the estimated value ofthe parameter of the lens for the particular relative angle is based onan image corresponding to the particular relative angle.
 8. The productof claim 5, wherein the instructions, when executed, cause the computingdevice to determine the first relative angle based on the first image,and to determine the second relative angle based on the second image. 9.The product of claim 5, wherein the instructions, when executed, causethe computing device to cause a user interface to instruct a user tomove the lens for capturing of the plurality of images at the pluralityof relative angles.
 10. The product of claim 1, wherein theinstructions, when executed, cause the computing device to determine theone or more parameters of the lens based on a first distance and asecond distance, the first distance is between the object and the imagecapturing device, the second distance is between the object and thelens.
 11. The product of claim 10, wherein the instructions, whenexecuted, cause the computing device to determine at least one of thefirst distance or the second distance based on an imaged referenceobject in the image captured by the image capturing device.
 12. Theproduct of claim 1, wherein the instructions, when executed, cause thecomputing device to determine the one or more parameters of the lensbased on a mirrored image of the object, wherein the image capturingdevice comprises a camera of a mobile device, the object comprises adisplayed object on a display of the mobile device, and the mirroredimage of the object comprises a reflection of the displayed object froma mirror.
 13. The product of claim 1, wherein the instructions, whenexecuted, cause the computing device to trigger a graphic display todisplay the object, and to trigger capturing of an image of the graphicdisplay by the image capturing device.
 14. The product of claim 1,wherein the object comprises a circularly symmetric object.
 15. Theproduct of claim 1, wherein the object comprises a plurality ofconcentric rings.
 16. The product of claim 1, wherein the one or moreparameters of the lens comprise a spherical power of the lens.
 17. Theproduct of claim 1, wherein the one or more parameters of the lenscomprise at least one of a cylindrical power of the lens or acylindrical axis of the lens.
 18. The product of claim 1, wherein theone or more parameters of the lens comprise at least one of a center ofthe lens or a pupillary distance (PD) corresponding to eyeglassescomprising the lens and another lens.
 19. An apparatus comprising: animage capturing device to capture an image; and a processor configuredto provide an output based on one or more parameters of a lens by:identifying an imaged object in the image captured by the imagecapturing device, the imaged object comprising an image of an object ascaptured by the image capturing device via the lens; determining anangle-based value, the angle-based value is based on a relative anglebetween a plane of the lens and a plane of the image capturing devicewhen the image is captured; and determining the one or more parametersof the lens based on the angle-based value and the imaged object. 20.The apparatus of claim 19, wherein the processor is configured todetermine the angle-based value based on one or more elements in theimage captured by the image capturing device.
 21. The apparatus of claim19, wherein the processor is configured to determine the one or moreparameters of the lens based on a plurality of images captured by theimage capturing device, the plurality of images corresponding to aplurality of relative angles between the plane of the lens and the planeof the image capturing device, wherein a first image in the plurality ofimages comprises a first image of the object as captured by the imagecapturing device via the lens at a first relative angle, and wherein asecond image in the plurality of images comprises a second image of theobject as captured by the image capturing device via the lens at asecond relative angle different from the first relative angle.
 22. Theapparatus of claim 21, wherein the processor is configured to cause auser interface to instruct a user to move the lens for capturing of theplurality of images at the plurality of relative angles.
 23. Theapparatus of claim 19, wherein the processor is configured to determinethe one or more parameters of the lens based on a first distance and asecond distance, the first distance is between the object and the imagecapturing device, the second distance is between the object and thelens.
 24. An apparatus comprising: means for determining one or moreparameters of a lens by: identifying an imaged object in an imagecaptured by the image capturing device, the imaged object comprising animage of an object as captured by the image capturing device via thelens; determining an angle-based value, the angle-based value is basedon a relative angle between a plane of the lens and a plane of the imagecapturing device when the image is captured; and determining the one ormore parameters of the lens based on the angle-based value and theimaged object; and means for providing an output based on the one ormore parameters of the lens.
 25. The apparatus of claim 24 comprisingmeans for determining the angle-based value based on one or moreelements in the image captured by the image capturing device.